diff --git a/metrics/libmetrics.gypi b/metrics/libmetrics.gypi
index 65de6f5..5b90a55 100644
--- a/metrics/libmetrics.gypi
+++ b/metrics/libmetrics.gypi
@@ -23,9 +23,9 @@
       'sources': [
         'c_metrics_library.cc',
         'metrics_library.cc',
+        'serialization/metric_sample.cc',
+        'serialization/serialization_utils.cc',
         'timer.cc',
-        'components/metrics/chromeos/metric_sample.cc',
-        'components/metrics/chromeos/serialization_utils.cc',
       ],
       'include_dirs': ['.'],
     },
diff --git a/metrics/metrics.gyp b/metrics/metrics.gyp
index cd07682..9614826 100644
--- a/metrics/metrics.gyp
+++ b/metrics/metrics.gyp
@@ -75,12 +75,11 @@
       },
       'sources': [
         'uploader/upload_service.cc',
+        'uploader/metrics_hashes.cc',
         'uploader/metrics_log.cc',
+        'uploader/metrics_log_base.cc',
         'uploader/system_profile_cache.cc',
         'uploader/sender_http.cc',
-        'components/metrics/metrics_log_base.cc',
-        'components/metrics/metrics_log_manager.cc',
-        'components/metrics/metrics_hashes.cc',
       ],
       'include_dirs': ['.']
     },
@@ -136,6 +135,7 @@
           'includes': ['../common-mk/common_test.gypi'],
           'sources': [
             'metrics_library_test.cc',
+            'serialization/serialization_utils_unittest.cc',
           ],
           'link_settings': {
             'libraries': [
@@ -157,6 +157,8 @@
           'type': 'executable',
           'sources': [
             'persistent_integer.cc',
+            'uploader/metrics_hashes_unittest.cc',
+            'uploader/metrics_log_base_unittest.cc',
             'uploader/mock/sender_mock.cc',
             'uploader/upload_service_test.cc',
           ],
diff --git a/metrics/metrics_library.cc b/metrics/metrics_library.cc
index c352bcf..5088cae 100644
--- a/metrics/metrics_library.cc
+++ b/metrics/metrics_library.cc
@@ -13,13 +13,11 @@
 #include <cstdio>
 #include <cstring>
 
-#include "components/metrics/chromeos/metric_sample.h"
-#include "components/metrics/chromeos/serialization_utils.h"
+#include "metrics/serialization/metric_sample.h"
+#include "metrics/serialization/serialization_utils.h"
 
 #include "policy/device_policy.h"
 
-#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
-
 static const char kAutotestPath[] = "/var/log/metrics/autotest-events";
 static const char kUMAEventsPath[] = "/var/run/metrics/uma-events";
 static const char kConsentFile[] = "/home/chronos/Consent To Send Stats";
@@ -206,7 +204,7 @@
 }
 
 bool MetricsLibrary::SendCrosEventToUMA(const std::string& event) {
-  for (size_t i = 0; i < ARRAY_SIZE(kCrosEventNames); i++) {
+  for (size_t i = 0; i < arraysize(kCrosEventNames); i++) {
     if (strcmp(event.c_str(), kCrosEventNames[i]) == 0) {
       return SendEnumToUMA(kCrosEventHistogramName, i, kCrosEventHistogramMax);
     }
diff --git a/metrics/serialization/metric_sample.cc b/metrics/serialization/metric_sample.cc
new file mode 100644
index 0000000..5447497
--- /dev/null
+++ b/metrics/serialization/metric_sample.cc
@@ -0,0 +1,197 @@
+// Copyright 2014 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "metrics/serialization/metric_sample.h"
+
+#include <string>
+#include <vector>
+
+#include "base/logging.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/string_split.h"
+#include "base/strings/stringprintf.h"
+
+namespace metrics {
+
+MetricSample::MetricSample(MetricSample::SampleType sample_type,
+                           const std::string& metric_name,
+                           int sample,
+                           int min,
+                           int max,
+                           int bucket_count)
+    : type_(sample_type),
+      name_(metric_name),
+      sample_(sample),
+      min_(min),
+      max_(max),
+      bucket_count_(bucket_count) {
+}
+
+MetricSample::~MetricSample() {
+}
+
+bool MetricSample::IsValid() const {
+  return name().find(' ') == std::string::npos &&
+         name().find('\0') == std::string::npos && !name().empty();
+}
+
+std::string MetricSample::ToString() const {
+  if (type_ == CRASH) {
+    return base::StringPrintf("crash%c%s%c",
+                              '\0',
+                              name().c_str(),
+                              '\0');
+  } else if (type_ == SPARSE_HISTOGRAM) {
+    return base::StringPrintf("sparsehistogram%c%s %d%c",
+                              '\0',
+                              name().c_str(),
+                              sample_,
+                              '\0');
+  } else if (type_ == LINEAR_HISTOGRAM) {
+    return base::StringPrintf("linearhistogram%c%s %d %d%c",
+                              '\0',
+                              name().c_str(),
+                              sample_,
+                              max_,
+                              '\0');
+  } else if (type_ == HISTOGRAM) {
+    return base::StringPrintf("histogram%c%s %d %d %d %d%c",
+                              '\0',
+                              name().c_str(),
+                              sample_,
+                              min_,
+                              max_,
+                              bucket_count_,
+                              '\0');
+  } else {
+    // The type can only be USER_ACTION.
+    CHECK_EQ(type_, USER_ACTION);
+    return base::StringPrintf("useraction%c%s%c",
+                              '\0',
+                              name().c_str(),
+                              '\0');
+  }
+}
+
+int MetricSample::sample() const {
+  CHECK_NE(type_, USER_ACTION);
+  CHECK_NE(type_, CRASH);
+  return sample_;
+}
+
+int MetricSample::min() const {
+  CHECK_EQ(type_, HISTOGRAM);
+  return min_;
+}
+
+int MetricSample::max() const {
+  CHECK_NE(type_, CRASH);
+  CHECK_NE(type_, USER_ACTION);
+  CHECK_NE(type_, SPARSE_HISTOGRAM);
+  return max_;
+}
+
+int MetricSample::bucket_count() const {
+  CHECK_EQ(type_, HISTOGRAM);
+  return bucket_count_;
+}
+
+// static
+scoped_ptr<MetricSample> MetricSample::CrashSample(
+    const std::string& crash_name) {
+  return scoped_ptr<MetricSample>(
+      new MetricSample(CRASH, crash_name, 0, 0, 0, 0));
+}
+
+// static
+scoped_ptr<MetricSample> MetricSample::HistogramSample(
+    const std::string& histogram_name,
+    int sample,
+    int min,
+    int max,
+    int bucket_count) {
+  return scoped_ptr<MetricSample>(new MetricSample(
+      HISTOGRAM, histogram_name, sample, min, max, bucket_count));
+}
+
+// static
+scoped_ptr<MetricSample> MetricSample::ParseHistogram(
+    const std::string& serialized_histogram) {
+  std::vector<std::string> parts;
+  base::SplitString(serialized_histogram, ' ', &parts);
+
+  if (parts.size() != 5)
+    return scoped_ptr<MetricSample>();
+  int sample, min, max, bucket_count;
+  if (parts[0].empty() || !base::StringToInt(parts[1], &sample) ||
+      !base::StringToInt(parts[2], &min) ||
+      !base::StringToInt(parts[3], &max) ||
+      !base::StringToInt(parts[4], &bucket_count)) {
+    return scoped_ptr<MetricSample>();
+  }
+
+  return HistogramSample(parts[0], sample, min, max, bucket_count);
+}
+
+// static
+scoped_ptr<MetricSample> MetricSample::SparseHistogramSample(
+    const std::string& histogram_name,
+    int sample) {
+  return scoped_ptr<MetricSample>(
+      new MetricSample(SPARSE_HISTOGRAM, histogram_name, sample, 0, 0, 0));
+}
+
+// static
+scoped_ptr<MetricSample> MetricSample::ParseSparseHistogram(
+    const std::string& serialized_histogram) {
+  std::vector<std::string> parts;
+  base::SplitString(serialized_histogram, ' ', &parts);
+  if (parts.size() != 2)
+    return scoped_ptr<MetricSample>();
+  int sample;
+  if (parts[0].empty() || !base::StringToInt(parts[1], &sample))
+    return scoped_ptr<MetricSample>();
+
+  return SparseHistogramSample(parts[0], sample);
+}
+
+// static
+scoped_ptr<MetricSample> MetricSample::LinearHistogramSample(
+    const std::string& histogram_name,
+    int sample,
+    int max) {
+  return scoped_ptr<MetricSample>(
+      new MetricSample(LINEAR_HISTOGRAM, histogram_name, sample, 0, max, 0));
+}
+
+// static
+scoped_ptr<MetricSample> MetricSample::ParseLinearHistogram(
+    const std::string& serialized_histogram) {
+  std::vector<std::string> parts;
+  int sample, max;
+  base::SplitString(serialized_histogram, ' ', &parts);
+  if (parts.size() != 3)
+    return scoped_ptr<MetricSample>();
+  if (parts[0].empty() || !base::StringToInt(parts[1], &sample) ||
+      !base::StringToInt(parts[2], &max)) {
+    return scoped_ptr<MetricSample>();
+  }
+
+  return LinearHistogramSample(parts[0], sample, max);
+}
+
+// static
+scoped_ptr<MetricSample> MetricSample::UserActionSample(
+    const std::string& action_name) {
+  return scoped_ptr<MetricSample>(
+      new MetricSample(USER_ACTION, action_name, 0, 0, 0, 0));
+}
+
+bool MetricSample::IsEqual(const MetricSample& metric) {
+  return type_ == metric.type_ && name_ == metric.name_ &&
+         sample_ == metric.sample_ && min_ == metric.min_ &&
+         max_ == metric.max_ && bucket_count_ == metric.bucket_count_;
+}
+
+}  // namespace metrics
diff --git a/metrics/serialization/metric_sample.h b/metrics/serialization/metric_sample.h
new file mode 100644
index 0000000..877114d
--- /dev/null
+++ b/metrics/serialization/metric_sample.h
@@ -0,0 +1,119 @@
+// Copyright 2014 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef METRICS_SERIALIZATION_METRIC_SAMPLE_H_
+#define METRICS_SERIALIZATION_METRIC_SAMPLE_H_
+
+#include <string>
+
+#include "base/gtest_prod_util.h"
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+
+namespace metrics {
+
+// This class is used by libmetrics (ChromeOS) to serialize
+// and deserialize measurements to send them to a metrics sending service.
+// It is meant to be a simple container with serialization functions.
+class MetricSample {
+ public:
+  // Types of metric sample used.
+  enum SampleType {
+    CRASH,
+    HISTOGRAM,
+    LINEAR_HISTOGRAM,
+    SPARSE_HISTOGRAM,
+    USER_ACTION
+  };
+
+  ~MetricSample();
+
+  // Returns true if the sample is valid (can be serialized without ambiguity).
+  //
+  // This function should be used to filter bad samples before serializing them.
+  bool IsValid() const;
+
+  // Getters for type and name. All types of metrics have these so we do not
+  // need to check the type.
+  SampleType type() const { return type_; }
+  const std::string& name() const { return name_; }
+
+  // Getters for sample, min, max, bucket_count.
+  // Check the metric type to make sure the request make sense. (ex: a crash
+  // sample does not have a bucket_count so we crash if we call bucket_count()
+  // on it.)
+  int sample() const;
+  int min() const;
+  int max() const;
+  int bucket_count() const;
+
+  // Returns a serialized version of the sample.
+  //
+  // The serialized message for each type is:
+  // crash: crash\0|name_|\0
+  // user action: useraction\0|name_|\0
+  // histogram: histogram\0|name_| |sample_| |min_| |max_| |bucket_count_|\0
+  // sparsehistogram: sparsehistogram\0|name_| |sample_|\0
+  // linearhistogram: linearhistogram\0|name_| |sample_| |max_|\0
+  std::string ToString() const;
+
+  // Builds a crash sample.
+  static scoped_ptr<MetricSample> CrashSample(const std::string& crash_name);
+
+  // Builds a histogram sample.
+  static scoped_ptr<MetricSample> HistogramSample(
+      const std::string& histogram_name,
+      int sample,
+      int min,
+      int max,
+      int bucket_count);
+  // Deserializes a histogram sample.
+  static scoped_ptr<MetricSample> ParseHistogram(const std::string& serialized);
+
+  // Builds a sparse histogram sample.
+  static scoped_ptr<MetricSample> SparseHistogramSample(
+      const std::string& histogram_name,
+      int sample);
+  // Deserializes a sparse histogram sample.
+  static scoped_ptr<MetricSample> ParseSparseHistogram(
+      const std::string& serialized);
+
+  // Builds a linear histogram sample.
+  static scoped_ptr<MetricSample> LinearHistogramSample(
+      const std::string& histogram_name,
+      int sample,
+      int max);
+  // Deserializes a linear histogram sample.
+  static scoped_ptr<MetricSample> ParseLinearHistogram(
+      const std::string& serialized);
+
+  // Builds a user action sample.
+  static scoped_ptr<MetricSample> UserActionSample(
+      const std::string& action_name);
+
+  // Returns true if sample and this object represent the same sample (type,
+  // name, sample, min, max, bucket_count match).
+  bool IsEqual(const MetricSample& sample);
+
+ private:
+  MetricSample(SampleType sample_type,
+               const std::string& metric_name,
+               const int sample,
+               const int min,
+               const int max,
+               const int bucket_count);
+
+  const SampleType type_;
+  const std::string name_;
+  const int sample_;
+  const int min_;
+  const int max_;
+  const int bucket_count_;
+
+  DISALLOW_COPY_AND_ASSIGN(MetricSample);
+};
+
+}  // namespace metrics
+
+#endif  // METRICS_SERIALIZATION_METRIC_SAMPLE_H_
diff --git a/metrics/serialization/serialization_utils.cc b/metrics/serialization/serialization_utils.cc
new file mode 100644
index 0000000..fea493e
--- /dev/null
+++ b/metrics/serialization/serialization_utils.cc
@@ -0,0 +1,216 @@
+// Copyright 2014 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "metrics/serialization/serialization_utils.h"
+
+#include <sys/file.h>
+
+#include <string>
+#include <vector>
+
+#include "base/file_util.h"
+#include "base/files/file_path.h"
+#include "base/files/scoped_file.h"
+#include "base/logging.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/scoped_vector.h"
+#include "base/strings/string_split.h"
+#include "base/strings/string_util.h"
+#include "metrics/serialization/metric_sample.h"
+
+#define READ_WRITE_ALL_FILE_FLAGS \
+  (S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)
+
+namespace metrics {
+namespace {
+
+// Reads the next message from |file_descriptor| into |message|.
+//
+// |message| will be set to the empty string if no message could be read (EOF)
+// or the message was badly constructed.
+//
+// Returns false if no message can be read from this file anymore (EOF or
+// unrecoverable error).
+bool ReadMessage(int fd, std::string* message) {
+  CHECK(message);
+
+  int result;
+  int32 message_size;
+  // The file containing the metrics do not leave the device so the writer and
+  // the reader will always have the same endianness.
+  result = HANDLE_EINTR(read(fd, &message_size, sizeof(message_size)));
+  if (result < 0) {
+    DPLOG(ERROR) << "reading metrics message header";
+    return false;
+  }
+  if (result == 0) {
+    // This indicates a normal EOF.
+    return false;
+  }
+  if (result < static_cast<int>(sizeof(message_size))) {
+    DLOG(ERROR) << "bad read size " << result << ", expecting "
+                << sizeof(message_size);
+    return false;
+  }
+
+  // kMessageMaxLength applies to the entire message: the 4-byte
+  // length field and the content.
+  if (message_size > SerializationUtils::kMessageMaxLength) {
+    DLOG(ERROR) << "message too long : " << message_size;
+    if (HANDLE_EINTR(lseek(fd, message_size - 4, SEEK_CUR)) == -1) {
+      DLOG(ERROR) << "error while skipping message. abort";
+      return false;
+    }
+    // Badly formatted message was skipped. Treat the badly formatted sample as
+    // an empty sample.
+    message->clear();
+    return true;
+  }
+
+  message_size -= sizeof(message_size);  // The message size includes itself.
+  char buffer[SerializationUtils::kMessageMaxLength];
+  if (!base::ReadFromFD(fd, buffer, message_size)) {
+    DPLOG(ERROR) << "reading metrics message body";
+    return false;
+  }
+  *message = std::string(buffer, message_size);
+  return true;
+}
+
+}  // namespace
+
+scoped_ptr<MetricSample> SerializationUtils::ParseSample(
+    const std::string& sample) {
+  if (sample.empty())
+    return scoped_ptr<MetricSample>();
+
+  std::vector<std::string> parts;
+  base::SplitString(sample, '\0', &parts);
+  // We should have two null terminated strings so split should produce
+  // three chunks.
+  if (parts.size() != 3) {
+    DLOG(ERROR) << "splitting message on \\0 produced " << parts.size()
+                << " parts (expected 3)";
+    return scoped_ptr<MetricSample>();
+  }
+  const std::string& name = parts[0];
+  const std::string& value = parts[1];
+
+  if (LowerCaseEqualsASCII(name, "crash")) {
+    return MetricSample::CrashSample(value);
+  } else if (LowerCaseEqualsASCII(name, "histogram")) {
+    return MetricSample::ParseHistogram(value);
+  } else if (LowerCaseEqualsASCII(name, "linearhistogram")) {
+    return MetricSample::ParseLinearHistogram(value);
+  } else if (LowerCaseEqualsASCII(name, "sparsehistogram")) {
+    return MetricSample::ParseSparseHistogram(value);
+  } else if (LowerCaseEqualsASCII(name, "useraction")) {
+    return MetricSample::UserActionSample(value);
+  } else {
+    DLOG(ERROR) << "invalid event type: " << name << ", value: " << value;
+  }
+  return scoped_ptr<MetricSample>();
+}
+
+void SerializationUtils::ReadAndTruncateMetricsFromFile(
+    const std::string& filename,
+    ScopedVector<MetricSample>* metrics) {
+  struct stat stat_buf;
+  int result;
+
+  result = stat(filename.c_str(), &stat_buf);
+  if (result < 0) {
+    if (errno != ENOENT)
+      DPLOG(ERROR) << filename << ": bad metrics file stat";
+
+    // Nothing to collect---try later.
+    return;
+  }
+  if (stat_buf.st_size == 0) {
+    // Also nothing to collect.
+    return;
+  }
+  base::ScopedFD fd(open(filename.c_str(), O_RDWR));
+  if (fd.get() < 0) {
+    DPLOG(ERROR) << filename << ": cannot open";
+    return;
+  }
+  result = flock(fd.get(), LOCK_EX);
+  if (result < 0) {
+    DPLOG(ERROR) << filename << ": cannot lock";
+    return;
+  }
+
+  // This processes all messages in the log. When all messages are
+  // read and processed, or an error occurs, truncate the file to zero size.
+  for (;;) {
+    std::string message;
+
+    if (!ReadMessage(fd.get(), &message))
+      break;
+
+    scoped_ptr<MetricSample> sample = ParseSample(message);
+    if (sample)
+      metrics->push_back(sample.release());
+  }
+
+  result = ftruncate(fd.get(), 0);
+  if (result < 0)
+    DPLOG(ERROR) << "truncate metrics log";
+
+  result = flock(fd.get(), LOCK_UN);
+  if (result < 0)
+    DPLOG(ERROR) << "unlock metrics log";
+}
+
+bool SerializationUtils::WriteMetricToFile(const MetricSample& sample,
+                                           const std::string& filename) {
+  if (!sample.IsValid())
+    return false;
+
+  base::ScopedFD file_descriptor(open(filename.c_str(),
+                                      O_WRONLY | O_APPEND | O_CREAT,
+                                      READ_WRITE_ALL_FILE_FLAGS));
+
+  if (file_descriptor.get() < 0) {
+    DLOG(ERROR) << "error openning the file";
+    return false;
+  }
+
+  fchmod(file_descriptor.get(), READ_WRITE_ALL_FILE_FLAGS);
+  // Grab a lock to avoid chrome truncating the file
+  // underneath us. Keep the file locked as briefly as possible.
+  // Freeing file_descriptor will close the file and and remove the lock.
+  if (HANDLE_EINTR(flock(file_descriptor.get(), LOCK_EX)) < 0) {
+    DLOG(ERROR) << "error locking" << filename << " : " << errno;
+    return false;
+  }
+
+  std::string msg = sample.ToString();
+  int32 size = msg.length() + sizeof(int32);
+  if (size > kMessageMaxLength) {
+    DLOG(ERROR) << "cannot write message: too long";
+    return false;
+  }
+
+  // The file containing the metrics samples will only be read by programs on
+  // the same device so we do not check endianness.
+  if (base::WriteFileDescriptor(file_descriptor.get(),
+                                 reinterpret_cast<char*>(&size),
+                                 sizeof(size)) != sizeof(size)) {
+    DPLOG(ERROR) << "error writing message length";
+    return false;
+  }
+
+  if (base::WriteFileDescriptor(
+          file_descriptor.get(), msg.c_str(), msg.size()) !=
+      static_cast<int>(msg.size())) {
+    DPLOG(ERROR) << "error writing message";
+    return false;
+  }
+
+  return true;
+}
+
+}  // namespace metrics
diff --git a/metrics/serialization/serialization_utils.h b/metrics/serialization/serialization_utils.h
new file mode 100644
index 0000000..5af6166
--- /dev/null
+++ b/metrics/serialization/serialization_utils.h
@@ -0,0 +1,48 @@
+// Copyright 2014 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef METRICS_SERIALIZATION_SERIALIZATION_UTILS_H_
+#define METRICS_SERIALIZATION_SERIALIZATION_UTILS_H_
+
+#include <string>
+
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/scoped_vector.h"
+
+namespace metrics {
+
+class MetricSample;
+
+// Metrics helpers to serialize and deserialize metrics collected by
+// ChromeOS.
+namespace SerializationUtils {
+
+// Deserializes a sample passed as a string and return a sample.
+// The return value will either be a scoped_ptr to a Metric sample (if the
+// deserialization was successful) or a NULL scoped_ptr.
+scoped_ptr<MetricSample> ParseSample(const std::string& sample);
+
+// Reads all samples from a file and truncate the file when done.
+void ReadAndTruncateMetricsFromFile(const std::string& filename,
+                                    ScopedVector<MetricSample>* metrics);
+
+// Serializes a sample and write it to filename.
+// The format for the message is:
+//  message_size, serialized_message
+// where
+//  * message_size is the total length of the message (message_size +
+//    serialized_message) on 4 bytes
+//  * serialized_message is the serialized version of sample (using ToString)
+//
+//  NB: the file will never leave the device so message_size will be written
+//  with the architecture's endianness.
+bool WriteMetricToFile(const MetricSample& sample, const std::string& filename);
+
+// Maximum length of a serialized message
+static const int kMessageMaxLength = 1024;
+
+}  // namespace SerializationUtils
+}  // namespace metrics
+
+#endif  // METRICS_SERIALIZATION_SERIALIZATION_UTILS_H_
diff --git a/metrics/serialization/serialization_utils_unittest.cc b/metrics/serialization/serialization_utils_unittest.cc
new file mode 100644
index 0000000..d47fbc8
--- /dev/null
+++ b/metrics/serialization/serialization_utils_unittest.cc
@@ -0,0 +1,169 @@
+// Copyright 2014 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "metrics/serialization/serialization_utils.h"
+
+#include <base/file_util.h>
+#include <base/files/scoped_temp_dir.h>
+#include <base/logging.h>
+#include <base/strings/stringprintf.h>
+#include <gtest/gtest.h>
+
+#include "metrics/serialization/metric_sample.h"
+
+namespace metrics {
+namespace {
+
+class SerializationUtilsTest : public testing::Test {
+ protected:
+  SerializationUtilsTest() {
+    bool success = temporary_dir.CreateUniqueTempDir();
+    if (success) {
+      base::FilePath dir_path = temporary_dir.path();
+      filename = dir_path.value() + "chromeossampletest";
+      filepath = base::FilePath(filename);
+    }
+  }
+
+  void SetUp() override { base::DeleteFile(filepath, false); }
+
+  void TestSerialization(MetricSample* sample) {
+    std::string serialized(sample->ToString());
+    ASSERT_EQ('\0', serialized[serialized.length() - 1]);
+    scoped_ptr<MetricSample> deserialized =
+        SerializationUtils::ParseSample(serialized);
+    ASSERT_TRUE(deserialized);
+    EXPECT_TRUE(sample->IsEqual(*deserialized.get()));
+  }
+
+  std::string filename;
+  base::ScopedTempDir temporary_dir;
+  base::FilePath filepath;
+};
+
+TEST_F(SerializationUtilsTest, CrashSerializeTest) {
+  TestSerialization(MetricSample::CrashSample("test").get());
+}
+
+TEST_F(SerializationUtilsTest, HistogramSerializeTest) {
+  TestSerialization(
+      MetricSample::HistogramSample("myhist", 13, 1, 100, 10).get());
+}
+
+TEST_F(SerializationUtilsTest, LinearSerializeTest) {
+  TestSerialization(
+      MetricSample::LinearHistogramSample("linearhist", 12, 30).get());
+}
+
+TEST_F(SerializationUtilsTest, SparseSerializeTest) {
+  TestSerialization(MetricSample::SparseHistogramSample("mysparse", 30).get());
+}
+
+TEST_F(SerializationUtilsTest, UserActionSerializeTest) {
+  TestSerialization(MetricSample::UserActionSample("myaction").get());
+}
+
+TEST_F(SerializationUtilsTest, IllegalNameAreFilteredTest) {
+  scoped_ptr<MetricSample> sample1 =
+      MetricSample::SparseHistogramSample("no space", 10);
+  scoped_ptr<MetricSample> sample2 = MetricSample::LinearHistogramSample(
+      base::StringPrintf("here%cbhe", '\0'), 1, 3);
+
+  EXPECT_FALSE(SerializationUtils::WriteMetricToFile(*sample1.get(), filename));
+  EXPECT_FALSE(SerializationUtils::WriteMetricToFile(*sample2.get(), filename));
+  int64 size = 0;
+
+  ASSERT_TRUE(!PathExists(filepath) || base::GetFileSize(filepath, &size));
+
+  EXPECT_EQ(0, size);
+}
+
+TEST_F(SerializationUtilsTest, BadInputIsCaughtTest) {
+  std::string input(
+      base::StringPrintf("sparsehistogram%cname foo%c", '\0', '\0'));
+  EXPECT_EQ(NULL, MetricSample::ParseSparseHistogram(input).get());
+}
+
+TEST_F(SerializationUtilsTest, MessageSeparatedByZero) {
+  scoped_ptr<MetricSample> crash = MetricSample::CrashSample("mycrash");
+
+  SerializationUtils::WriteMetricToFile(*crash.get(), filename);
+  int64 size = 0;
+  ASSERT_TRUE(base::GetFileSize(filepath, &size));
+  // 4 bytes for the size
+  // 5 bytes for crash
+  // 7 bytes for mycrash
+  // 2 bytes for the \0
+  // -> total of 18
+  EXPECT_EQ(size, 18);
+}
+
+TEST_F(SerializationUtilsTest, MessagesTooLongAreDiscardedTest) {
+  // Creates a message that is bigger than the maximum allowed size.
+  // As we are adding extra character (crash, \0s, etc), if the name is
+  // kMessageMaxLength long, it will be too long.
+  std::string name(SerializationUtils::kMessageMaxLength, 'c');
+
+  scoped_ptr<MetricSample> crash = MetricSample::CrashSample(name);
+  EXPECT_FALSE(SerializationUtils::WriteMetricToFile(*crash.get(), filename));
+  int64 size = 0;
+  ASSERT_TRUE(base::GetFileSize(filepath, &size));
+  EXPECT_EQ(0, size);
+}
+
+TEST_F(SerializationUtilsTest, ReadLongMessageTest) {
+  base::File test_file(filepath,
+                       base::File::FLAG_OPEN_ALWAYS | base::File::FLAG_APPEND);
+  std::string message(SerializationUtils::kMessageMaxLength + 1, 'c');
+
+  int32 message_size = message.length() + sizeof(int32);
+  test_file.WriteAtCurrentPos(reinterpret_cast<const char*>(&message_size),
+                              sizeof(message_size));
+  test_file.WriteAtCurrentPos(message.c_str(), message.length());
+  test_file.Close();
+
+  scoped_ptr<MetricSample> crash = MetricSample::CrashSample("test");
+  SerializationUtils::WriteMetricToFile(*crash.get(), filename);
+
+  ScopedVector<MetricSample> samples;
+  SerializationUtils::ReadAndTruncateMetricsFromFile(filename, &samples);
+  ASSERT_EQ(size_t(1), samples.size());
+  ASSERT_TRUE(samples[0] != NULL);
+  EXPECT_TRUE(crash->IsEqual(*samples[0]));
+}
+
+TEST_F(SerializationUtilsTest, WriteReadTest) {
+  scoped_ptr<MetricSample> hist =
+      MetricSample::HistogramSample("myhist", 1, 2, 3, 4);
+  scoped_ptr<MetricSample> crash = MetricSample::CrashSample("mycrash");
+  scoped_ptr<MetricSample> lhist =
+      MetricSample::LinearHistogramSample("linear", 1, 10);
+  scoped_ptr<MetricSample> shist =
+      MetricSample::SparseHistogramSample("mysparse", 30);
+  scoped_ptr<MetricSample> action = MetricSample::UserActionSample("myaction");
+
+  SerializationUtils::WriteMetricToFile(*hist.get(), filename);
+  SerializationUtils::WriteMetricToFile(*crash.get(), filename);
+  SerializationUtils::WriteMetricToFile(*lhist.get(), filename);
+  SerializationUtils::WriteMetricToFile(*shist.get(), filename);
+  SerializationUtils::WriteMetricToFile(*action.get(), filename);
+  ScopedVector<MetricSample> vect;
+  SerializationUtils::ReadAndTruncateMetricsFromFile(filename, &vect);
+  ASSERT_EQ(vect.size(), size_t(5));
+  for (int i = 0; i < 5; i++) {
+    ASSERT_TRUE(vect[0] != NULL);
+  }
+  EXPECT_TRUE(hist->IsEqual(*vect[0]));
+  EXPECT_TRUE(crash->IsEqual(*vect[1]));
+  EXPECT_TRUE(lhist->IsEqual(*vect[2]));
+  EXPECT_TRUE(shist->IsEqual(*vect[3]));
+  EXPECT_TRUE(action->IsEqual(*vect[4]));
+
+  int64 size = 0;
+  ASSERT_TRUE(base::GetFileSize(filepath, &size));
+  ASSERT_EQ(0, size);
+}
+
+}  // namespace
+}  // namespace metrics
diff --git a/metrics/uploader/metrics_hashes.cc b/metrics/uploader/metrics_hashes.cc
new file mode 100644
index 0000000..87405a3
--- /dev/null
+++ b/metrics/uploader/metrics_hashes.cc
@@ -0,0 +1,39 @@
+// Copyright 2014 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "metrics/uploader/metrics_hashes.h"
+
+#include "base/logging.h"
+#include "base/md5.h"
+#include "base/sys_byteorder.h"
+
+namespace metrics {
+
+namespace {
+
+// Converts the 8-byte prefix of an MD5 hash into a uint64 value.
+inline uint64_t HashToUInt64(const std::string& hash) {
+  uint64_t value;
+  DCHECK_GE(hash.size(), sizeof(value));
+  memcpy(&value, hash.data(), sizeof(value));
+  return base::HostToNet64(value);
+}
+
+}  // namespace
+
+uint64_t HashMetricName(const std::string& name) {
+  // Create an MD5 hash of the given |name|, represented as a byte buffer
+  // encoded as an std::string.
+  base::MD5Context context;
+  base::MD5Init(&context);
+  base::MD5Update(&context, name);
+
+  base::MD5Digest digest;
+  base::MD5Final(&digest, &context);
+
+  std::string hash_str(reinterpret_cast<char*>(digest.a), arraysize(digest.a));
+  return HashToUInt64(hash_str);
+}
+
+}  // namespace metrics
diff --git a/metrics/uploader/metrics_hashes.h b/metrics/uploader/metrics_hashes.h
new file mode 100644
index 0000000..8679077
--- /dev/null
+++ b/metrics/uploader/metrics_hashes.h
@@ -0,0 +1,18 @@
+// Copyright 2014 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef METRICS_UPLOADER_METRICS_HASHES_H_
+#define METRICS_UPLOADER_METRICS_HASHES_H_
+
+#include <string>
+
+namespace metrics {
+
+// Computes a uint64 hash of a given string based on its MD5 hash. Suitable for
+// metric names.
+uint64_t HashMetricName(const std::string& name);
+
+}  // namespace metrics
+
+#endif  // METRICS_UPLOADER_METRICS_HASHES_H_
diff --git a/metrics/uploader/metrics_hashes_unittest.cc b/metrics/uploader/metrics_hashes_unittest.cc
new file mode 100644
index 0000000..f7e390f
--- /dev/null
+++ b/metrics/uploader/metrics_hashes_unittest.cc
@@ -0,0 +1,32 @@
+// Copyright 2014 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "metrics/uploader/metrics_hashes.h"
+
+#include <base/format_macros.h>
+#include <base/macros.h>
+#include <base/strings/stringprintf.h>
+#include <gtest/gtest.h>
+
+namespace metrics {
+
+// Make sure our ID hashes are the same as what we see on the server side.
+TEST(MetricsUtilTest, HashMetricName) {
+  static const struct {
+    std::string input;
+    std::string output;
+  } cases[] = {
+    {"Back", "0x0557fa923dcee4d0"},
+    {"Forward", "0x67d2f6740a8eaebf"},
+    {"NewTab", "0x290eb683f96572f1"},
+  };
+
+  for (size_t i = 0; i < arraysize(cases); ++i) {
+    uint64_t hash = HashMetricName(cases[i].input);
+    std::string hash_hex = base::StringPrintf("0x%016" PRIx64, hash);
+    EXPECT_EQ(cases[i].output, hash_hex);
+  }
+}
+
+}  // namespace metrics
diff --git a/metrics/uploader/metrics_log.h b/metrics/uploader/metrics_log.h
index 37a82bd..5796325 100644
--- a/metrics/uploader/metrics_log.h
+++ b/metrics/uploader/metrics_log.h
@@ -9,7 +9,7 @@
 
 #include <base/macros.h>
 
-#include "components/metrics/metrics_log_base.h"
+#include "metrics/uploader/metrics_log_base.h"
 
 // This file defines a set of user experience metrics data recorded by
 // the MetricsService. This is the unit of data that is sent to the server.
diff --git a/metrics/uploader/metrics_log_base.cc b/metrics/uploader/metrics_log_base.cc
new file mode 100644
index 0000000..43cf82e
--- /dev/null
+++ b/metrics/uploader/metrics_log_base.cc
@@ -0,0 +1,142 @@
+// Copyright 2014 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "metrics/uploader/metrics_log_base.h"
+
+#include "base/metrics/histogram_base.h"
+#include "base/metrics/histogram_samples.h"
+#include "components/metrics/proto/histogram_event.pb.h"
+#include "components/metrics/proto/system_profile.pb.h"
+#include "components/metrics/proto/user_action_event.pb.h"
+#include "metrics/uploader/metrics_hashes.h"
+
+using base::Histogram;
+using base::HistogramBase;
+using base::HistogramSamples;
+using base::SampleCountIterator;
+using base::Time;
+using base::TimeDelta;
+using metrics::HistogramEventProto;
+using metrics::SystemProfileProto;
+using metrics::UserActionEventProto;
+
+namespace metrics {
+namespace {
+
+// Any id less than 16 bytes is considered to be a testing id.
+bool IsTestingID(const std::string& id) {
+  return id.size() < 16;
+}
+
+}  // namespace
+
+MetricsLogBase::MetricsLogBase(const std::string& client_id,
+                               int session_id,
+                               LogType log_type,
+                               const std::string& version_string)
+    : num_events_(0),
+      locked_(false),
+      log_type_(log_type) {
+  DCHECK_NE(NO_LOG, log_type);
+  if (IsTestingID(client_id))
+    uma_proto_.set_client_id(0);
+  else
+    uma_proto_.set_client_id(Hash(client_id));
+
+  uma_proto_.set_session_id(session_id);
+  uma_proto_.mutable_system_profile()->set_build_timestamp(GetBuildTime());
+  uma_proto_.mutable_system_profile()->set_app_version(version_string);
+}
+
+MetricsLogBase::~MetricsLogBase() {}
+
+// static
+uint64_t MetricsLogBase::Hash(const std::string& value) {
+  uint64_t hash = metrics::HashMetricName(value);
+
+  // The following log is VERY helpful when folks add some named histogram into
+  // the code, but forgot to update the descriptive list of histograms.  When
+  // that happens, all we get to see (server side) is a hash of the histogram
+  // name.  We can then use this logging to find out what histogram name was
+  // being hashed to a given MD5 value by just running the version of Chromium
+  // in question with --enable-logging.
+  DVLOG(1) << "Metrics: Hash numeric [" << value << "]=[" << hash << "]";
+
+  return hash;
+}
+
+// static
+int64_t MetricsLogBase::GetBuildTime() {
+  static int64_t integral_build_time = 0;
+  if (!integral_build_time) {
+    Time time;
+    const char* kDateTime = __DATE__ " " __TIME__ " GMT";
+    bool result = Time::FromString(kDateTime, &time);
+    DCHECK(result);
+    integral_build_time = static_cast<int64_t>(time.ToTimeT());
+  }
+  return integral_build_time;
+}
+
+// static
+int64_t MetricsLogBase::GetCurrentTime() {
+  return (base::TimeTicks::Now() - base::TimeTicks()).InSeconds();
+}
+
+void MetricsLogBase::CloseLog() {
+  DCHECK(!locked_);
+  locked_ = true;
+}
+
+void MetricsLogBase::GetEncodedLog(std::string* encoded_log) {
+  DCHECK(locked_);
+  uma_proto_.SerializeToString(encoded_log);
+}
+
+void MetricsLogBase::RecordUserAction(const std::string& key) {
+  DCHECK(!locked_);
+
+  UserActionEventProto* user_action = uma_proto_.add_user_action_event();
+  user_action->set_name_hash(Hash(key));
+  user_action->set_time(GetCurrentTime());
+
+  ++num_events_;
+}
+
+void MetricsLogBase::RecordHistogramDelta(const std::string& histogram_name,
+                                          const HistogramSamples& snapshot) {
+  DCHECK(!locked_);
+  DCHECK_NE(0, snapshot.TotalCount());
+
+  // We will ignore the MAX_INT/infinite value in the last element of range[].
+
+  HistogramEventProto* histogram_proto = uma_proto_.add_histogram_event();
+  histogram_proto->set_name_hash(Hash(histogram_name));
+  histogram_proto->set_sum(snapshot.sum());
+
+  for (scoped_ptr<SampleCountIterator> it = snapshot.Iterator(); !it->Done();
+       it->Next()) {
+    HistogramBase::Sample min;
+    HistogramBase::Sample max;
+    HistogramBase::Count count;
+    it->Get(&min, &max, &count);
+    HistogramEventProto::Bucket* bucket = histogram_proto->add_bucket();
+    bucket->set_min(min);
+    bucket->set_max(max);
+    bucket->set_count(count);
+  }
+
+  // Omit fields to save space (see rules in histogram_event.proto comments).
+  for (int i = 0; i < histogram_proto->bucket_size(); ++i) {
+    HistogramEventProto::Bucket* bucket = histogram_proto->mutable_bucket(i);
+    if (i + 1 < histogram_proto->bucket_size() &&
+        bucket->max() == histogram_proto->bucket(i + 1).min()) {
+      bucket->clear_max();
+    } else if (bucket->max() == bucket->min() + 1) {
+      bucket->clear_min();
+    }
+  }
+}
+
+}  // namespace metrics
diff --git a/metrics/uploader/metrics_log_base.h b/metrics/uploader/metrics_log_base.h
new file mode 100644
index 0000000..5a54c30
--- /dev/null
+++ b/metrics/uploader/metrics_log_base.h
@@ -0,0 +1,110 @@
+// Copyright 2014 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// This file defines a set of user experience metrics data recorded by
+// the MetricsService.  This is the unit of data that is sent to the server.
+
+#ifndef METRICS_UPLOADER_METRICS_LOG_BASE_H_
+#define METRICS_UPLOADER_METRICS_LOG_BASE_H_
+
+#include <string>
+
+#include "base/macros.h"
+#include "base/metrics/histogram.h"
+#include "base/time/time.h"
+#include "components/metrics/proto/chrome_user_metrics_extension.pb.h"
+
+namespace base {
+class HistogramSamples;
+}  // namespace base
+
+namespace metrics {
+
+// This class provides base functionality for logging metrics data.
+class MetricsLogBase {
+ public:
+  // TODO(asvitkine): Remove the NO_LOG value.
+  enum LogType {
+    INITIAL_STABILITY_LOG,  // The initial log containing stability stats.
+    ONGOING_LOG,            // Subsequent logs in a session.
+    NO_LOG,                 // Placeholder value for when there is no log.
+  };
+
+  // Creates a new metrics log of the specified type.
+  // client_id is the identifier for this profile on this installation
+  // session_id is an integer that's incremented on each application launch
+  MetricsLogBase(const std::string& client_id,
+                 int session_id,
+                 LogType log_type,
+                 const std::string& version_string);
+  virtual ~MetricsLogBase();
+
+  // Computes the MD5 hash of the given string, and returns the first 8 bytes of
+  // the hash.
+  static uint64_t Hash(const std::string& value);
+
+  // Get the GMT buildtime for the current binary, expressed in seconds since
+  // January 1, 1970 GMT.
+  // The value is used to identify when a new build is run, so that previous
+  // reliability stats, from other builds, can be abandoned.
+  static int64_t GetBuildTime();
+
+  // Convenience function to return the current time at a resolution in seconds.
+  // This wraps base::TimeTicks, and hence provides an abstract time that is
+  // always incrementing for use in measuring time durations.
+  static int64_t GetCurrentTime();
+
+  // Records a user-initiated action.
+  void RecordUserAction(const std::string& key);
+
+  // Record any changes in a given histogram for transmission.
+  void RecordHistogramDelta(const std::string& histogram_name,
+                            const base::HistogramSamples& snapshot);
+
+  // Stop writing to this record and generate the encoded representation.
+  // None of the Record* methods can be called after this is called.
+  void CloseLog();
+
+  // Fills |encoded_log| with the serialized protobuf representation of the
+  // record.  Must only be called after CloseLog() has been called.
+  void GetEncodedLog(std::string* encoded_log);
+
+  int num_events() { return num_events_; }
+
+  void set_hardware_class(const std::string& hardware_class) {
+    uma_proto_.mutable_system_profile()->mutable_hardware()->set_hardware_class(
+        hardware_class);
+  }
+
+  LogType log_type() const { return log_type_; }
+
+ protected:
+  bool locked() const { return locked_; }
+
+  metrics::ChromeUserMetricsExtension* uma_proto() { return &uma_proto_; }
+  const metrics::ChromeUserMetricsExtension* uma_proto() const {
+    return &uma_proto_;
+  }
+
+  // TODO(isherman): Remove this once the XML pipeline is outta here.
+  int num_events_;  // the number of events recorded in this log
+
+ private:
+  // locked_ is true when record has been packed up for sending, and should
+  // no longer be written to.  It is only used for sanity checking and is
+  // not a real lock.
+  bool locked_;
+
+  // The type of the log, i.e. initial or ongoing.
+  const LogType log_type_;
+
+  // Stores the protocol buffer representation for this log.
+  metrics::ChromeUserMetricsExtension uma_proto_;
+
+  DISALLOW_COPY_AND_ASSIGN(MetricsLogBase);
+};
+
+}  // namespace metrics
+
+#endif  // METRICS_UPLOADER_METRICS_LOG_BASE_H_
diff --git a/metrics/uploader/metrics_log_base_unittest.cc b/metrics/uploader/metrics_log_base_unittest.cc
new file mode 100644
index 0000000..fe02fea
--- /dev/null
+++ b/metrics/uploader/metrics_log_base_unittest.cc
@@ -0,0 +1,126 @@
+// Copyright 2014 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "metrics/uploader/metrics_log_base.h"
+
+#include <string>
+
+#include <base/base64.h>
+#include <base/metrics/bucket_ranges.h>
+#include <base/metrics/sample_vector.h>
+#include <gtest/gtest.h>
+
+#include "components/metrics/proto/chrome_user_metrics_extension.pb.h"
+
+namespace metrics {
+
+namespace {
+
+class TestMetricsLogBase : public MetricsLogBase {
+ public:
+  TestMetricsLogBase()
+      : MetricsLogBase("client_id", 1, MetricsLogBase::ONGOING_LOG, "1.2.3.4") {
+  }
+  virtual ~TestMetricsLogBase() {}
+
+  using MetricsLogBase::uma_proto;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(TestMetricsLogBase);
+};
+
+}  // namespace
+
+TEST(MetricsLogBaseTest, LogType) {
+  MetricsLogBase log1("id", 0, MetricsLogBase::ONGOING_LOG, "1.2.3");
+  EXPECT_EQ(MetricsLogBase::ONGOING_LOG, log1.log_type());
+
+  MetricsLogBase log2("id", 0, MetricsLogBase::INITIAL_STABILITY_LOG, "1.2.3");
+  EXPECT_EQ(MetricsLogBase::INITIAL_STABILITY_LOG, log2.log_type());
+}
+
+TEST(MetricsLogBaseTest, EmptyRecord) {
+  MetricsLogBase log("totally bogus client ID", 137,
+                     MetricsLogBase::ONGOING_LOG, "bogus version");
+  log.set_hardware_class("sample-class");
+  log.CloseLog();
+
+  std::string encoded;
+  log.GetEncodedLog(&encoded);
+
+  // A couple of fields are hard to mock, so these will be copied over directly
+  // for the expected output.
+  metrics::ChromeUserMetricsExtension parsed;
+  ASSERT_TRUE(parsed.ParseFromString(encoded));
+
+  metrics::ChromeUserMetricsExtension expected;
+  expected.set_client_id(5217101509553811875);  // Hashed bogus client ID
+  expected.set_session_id(137);
+  expected.mutable_system_profile()->set_build_timestamp(
+      parsed.system_profile().build_timestamp());
+  expected.mutable_system_profile()->set_app_version("bogus version");
+  expected.mutable_system_profile()->mutable_hardware()->set_hardware_class(
+      "sample-class");
+
+  EXPECT_EQ(expected.SerializeAsString(), encoded);
+}
+
+TEST(MetricsLogBaseTest, HistogramBucketFields) {
+  // Create buckets: 1-5, 5-7, 7-8, 8-9, 9-10, 10-11, 11-12.
+  base::BucketRanges ranges(8);
+  ranges.set_range(0, 1);
+  ranges.set_range(1, 5);
+  ranges.set_range(2, 7);
+  ranges.set_range(3, 8);
+  ranges.set_range(4, 9);
+  ranges.set_range(5, 10);
+  ranges.set_range(6, 11);
+  ranges.set_range(7, 12);
+
+  base::SampleVector samples(&ranges);
+  samples.Accumulate(3, 1);   // Bucket 1-5.
+  samples.Accumulate(6, 1);   // Bucket 5-7.
+  samples.Accumulate(8, 1);   // Bucket 8-9. (7-8 skipped)
+  samples.Accumulate(10, 1);  // Bucket 10-11. (9-10 skipped)
+  samples.Accumulate(11, 1);  // Bucket 11-12.
+
+  TestMetricsLogBase log;
+  log.RecordHistogramDelta("Test", samples);
+
+  const metrics::ChromeUserMetricsExtension* uma_proto = log.uma_proto();
+  const metrics::HistogramEventProto& histogram_proto =
+      uma_proto->histogram_event(uma_proto->histogram_event_size() - 1);
+
+  // Buckets with samples: 1-5, 5-7, 8-9, 10-11, 11-12.
+  // Should become: 1-/, 5-7, /-9, 10-/, /-12.
+  ASSERT_EQ(5, histogram_proto.bucket_size());
+
+  // 1-5 becomes 1-/ (max is same as next min).
+  EXPECT_TRUE(histogram_proto.bucket(0).has_min());
+  EXPECT_FALSE(histogram_proto.bucket(0).has_max());
+  EXPECT_EQ(1, histogram_proto.bucket(0).min());
+
+  // 5-7 stays 5-7 (no optimization possible).
+  EXPECT_TRUE(histogram_proto.bucket(1).has_min());
+  EXPECT_TRUE(histogram_proto.bucket(1).has_max());
+  EXPECT_EQ(5, histogram_proto.bucket(1).min());
+  EXPECT_EQ(7, histogram_proto.bucket(1).max());
+
+  // 8-9 becomes /-9 (min is same as max - 1).
+  EXPECT_FALSE(histogram_proto.bucket(2).has_min());
+  EXPECT_TRUE(histogram_proto.bucket(2).has_max());
+  EXPECT_EQ(9, histogram_proto.bucket(2).max());
+
+  // 10-11 becomes 10-/ (both optimizations apply, omit max is prioritized).
+  EXPECT_TRUE(histogram_proto.bucket(3).has_min());
+  EXPECT_FALSE(histogram_proto.bucket(3).has_max());
+  EXPECT_EQ(10, histogram_proto.bucket(3).min());
+
+  // 11-12 becomes /-12 (last record must keep max, min is same as max - 1).
+  EXPECT_FALSE(histogram_proto.bucket(4).has_min());
+  EXPECT_TRUE(histogram_proto.bucket(4).has_max());
+  EXPECT_EQ(12, histogram_proto.bucket(4).max());
+}
+
+}  // namespace metrics
diff --git a/metrics/uploader/system_profile_cache.cc b/metrics/uploader/system_profile_cache.cc
index cbb8051..be3d8ec 100644
--- a/metrics/uploader/system_profile_cache.cc
+++ b/metrics/uploader/system_profile_cache.cc
@@ -13,9 +13,9 @@
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/sys_info.h"
-#include "components/metrics/metrics_log_base.h"
 #include "components/metrics/proto/chrome_user_metrics_extension.pb.h"
 #include "metrics/persistent_integer.h"
+#include "metrics/uploader/metrics_log_base.h"
 #include "vboot/crossystem.h"
 
 namespace {
diff --git a/metrics/uploader/upload_service.cc b/metrics/uploader/upload_service.cc
index 7e856f9..cdec91e 100644
--- a/metrics/uploader/upload_service.cc
+++ b/metrics/uploader/upload_service.cc
@@ -15,9 +15,9 @@
 #include <base/metrics/sparse_histogram.h>
 #include <base/metrics/statistics_recorder.h>
 #include <base/sha1.h>
-#include <components/metrics/chromeos/metric_sample.h>
-#include <components/metrics/chromeos/serialization_utils.h>
 
+#include "metrics/serialization/metric_sample.h"
+#include "metrics/serialization/serialization_utils.h"
 #include "metrics/uploader/metrics_log.h"
 #include "metrics/uploader/sender_http.h"
 #include "metrics/uploader/system_profile_cache.h"
diff --git a/metrics/uploader/upload_service_test.cc b/metrics/uploader/upload_service_test.cc
index c48747e..ff96f85 100644
--- a/metrics/uploader/upload_service_test.cc
+++ b/metrics/uploader/upload_service_test.cc
@@ -9,15 +9,15 @@
 #include "base/files/scoped_temp_dir.h"
 #include "base/logging.h"
 #include "base/sys_info.h"
-#include "components/metrics/chromeos/metric_sample.h"
 #include "components/metrics/proto/chrome_user_metrics_extension.pb.h"
 #include "components/metrics/proto/histogram_event.pb.h"
 #include "components/metrics/proto/system_profile.pb.h"
-#include "uploader/metrics_log.h"
-#include "uploader/mock/mock_system_profile_setter.h"
-#include "uploader/mock/sender_mock.h"
-#include "uploader/system_profile_cache.h"
-#include "uploader/upload_service.h"
+#include "metrics/serialization/metric_sample.h"
+#include "metrics/uploader/metrics_log.h"
+#include "metrics/uploader/mock/mock_system_profile_setter.h"
+#include "metrics/uploader/mock/sender_mock.h"
+#include "metrics/uploader/system_profile_cache.h"
+#include "metrics/uploader/upload_service.h"
 
 static const char kMetricsServer[] = "https://clients4.google.com/uma/v2";
 static const char kMetricsFilePath[] = "/var/run/metrics/uma-events";