diff --git a/prefs_unittest.cc b/prefs_unittest.cc
index d2a07ee..a3595a3 100644
--- a/prefs_unittest.cc
+++ b/prefs_unittest.cc
@@ -8,8 +8,8 @@
 
 #include "base/basictypes.h"
 #include "base/file_util.h"
-#include "base/string_util.h"
-#include "base/stringprintf.h"
+#include <base/strings/string_util.h>
+#include <base/strings/stringprintf.h>
 #include "gtest/gtest.h"
 #include "update_engine/prefs.h"
 
@@ -20,12 +20,12 @@
 class PrefsTest : public ::testing::Test {
  protected:
   virtual void SetUp() {
-    ASSERT_TRUE(file_util::CreateNewTempDirectory("auprefs", &prefs_dir_));
+    ASSERT_TRUE(base::CreateNewTempDirectory("auprefs", &prefs_dir_));
     ASSERT_TRUE(prefs_.Init(prefs_dir_));
   }
 
   virtual void TearDown() {
-    file_util::Delete(prefs_dir_, true);  // recursive
+    base::DeleteFile(prefs_dir_, true);  // recursive
   }
 
   bool SetValue(const string& key, const string& value) {
@@ -34,24 +34,24 @@
         static_cast<int>(value.length());
   }
 
-  FilePath prefs_dir_;
+  base::FilePath prefs_dir_;
   Prefs prefs_;
 };
 
 TEST_F(PrefsTest, GetFileNameForKey) {
   const char kKey[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz_-";
-  FilePath path;
+  base::FilePath path;
   EXPECT_TRUE(prefs_.GetFileNameForKey(kKey, &path));
   EXPECT_EQ(prefs_dir_.Append(kKey).value(), path.value());
 }
 
 TEST_F(PrefsTest, GetFileNameForKeyBadCharacter) {
-  FilePath path;
+  base::FilePath path;
   EXPECT_FALSE(prefs_.GetFileNameForKey("ABC abc", &path));
 }
 
 TEST_F(PrefsTest, GetFileNameForKeyEmpty) {
-  FilePath path;
+  base::FilePath path;
   EXPECT_FALSE(prefs_.GetFileNameForKey("", &path));
 }
 
@@ -79,38 +79,38 @@
   const char kValue[] = "some test value\non 2 lines";
   EXPECT_TRUE(prefs_.SetString(kKey, kValue));
   string value;
-  EXPECT_TRUE(file_util::ReadFileToString(prefs_dir_.Append(kKey), &value));
+  EXPECT_TRUE(base::ReadFileToString(prefs_dir_.Append(kKey), &value));
   EXPECT_EQ(kValue, value);
 }
 
 TEST_F(PrefsTest, SetStringBadKey) {
   const char kKey[] = ".no-dots";
   EXPECT_FALSE(prefs_.SetString(kKey, "some value"));
-  EXPECT_FALSE(file_util::PathExists(prefs_dir_.Append(kKey)));
+  EXPECT_FALSE(base::PathExists(prefs_dir_.Append(kKey)));
 }
 
 TEST_F(PrefsTest, SetStringCreateDir) {
   const char kKey[] = "a-test-key";
   const char kValue[] = "test value";
-  FilePath subdir = prefs_dir_.Append("subdir1").Append("subdir2");
+  base::FilePath subdir = prefs_dir_.Append("subdir1").Append("subdir2");
   EXPECT_TRUE(prefs_.Init(subdir));
   EXPECT_TRUE(prefs_.SetString(kKey, kValue));
   string value;
-  EXPECT_TRUE(file_util::ReadFileToString(subdir.Append(kKey), &value));
+  EXPECT_TRUE(base::ReadFileToString(subdir.Append(kKey), &value));
   EXPECT_EQ(kValue, value);
 }
 
 TEST_F(PrefsTest, SetStringDirCreationFailure) {
-  EXPECT_TRUE(prefs_.Init(FilePath("/dev/null")));
+  EXPECT_TRUE(prefs_.Init(base::FilePath("/dev/null")));
   const char kKey[] = "test-key";
   EXPECT_FALSE(prefs_.SetString(kKey, "test value"));
 }
 
 TEST_F(PrefsTest, SetStringFileCreationFailure) {
   const char kKey[] = "a-test-key";
-  file_util::CreateDirectory(prefs_dir_.Append(kKey));
+  base::CreateDirectory(prefs_dir_.Append(kKey));
   EXPECT_FALSE(prefs_.SetString(kKey, "test value"));
-  EXPECT_TRUE(file_util::DirectoryExists(prefs_dir_.Append(kKey)));
+  EXPECT_TRUE(base::DirectoryExists(prefs_dir_.Append(kKey)));
 }
 
 TEST_F(PrefsTest, GetInt64) {
@@ -130,7 +130,7 @@
 
 TEST_F(PrefsTest, GetInt64Max) {
   const char kKey[] = "test-key";
-  ASSERT_TRUE(SetValue(kKey, StringPrintf("%" PRIi64, kint64max)));
+  ASSERT_TRUE(SetValue(kKey, base::StringPrintf("%" PRIi64, kint64max)));
   int64_t value;
   EXPECT_TRUE(prefs_.GetInt64(kKey, &value));
   EXPECT_EQ(kint64max, value);
@@ -138,7 +138,7 @@
 
 TEST_F(PrefsTest, GetInt64Min) {
   const char kKey[] = "test-key";
-  ASSERT_TRUE(SetValue(kKey, StringPrintf("%" PRIi64, kint64min)));
+  ASSERT_TRUE(SetValue(kKey, base::StringPrintf("%" PRIi64, kint64min)));
   int64_t value;
   EXPECT_TRUE(prefs_.GetInt64(kKey, &value));
   EXPECT_EQ(kint64min, value);
@@ -161,30 +161,30 @@
   const char kKey[] = "test_int";
   EXPECT_TRUE(prefs_.SetInt64(kKey, -123));
   string value;
-  EXPECT_TRUE(file_util::ReadFileToString(prefs_dir_.Append(kKey), &value));
+  EXPECT_TRUE(base::ReadFileToString(prefs_dir_.Append(kKey), &value));
   EXPECT_EQ("-123", value);
 }
 
 TEST_F(PrefsTest, SetInt64BadKey) {
   const char kKey[] = "s p a c e s";
   EXPECT_FALSE(prefs_.SetInt64(kKey, 20));
-  EXPECT_FALSE(file_util::PathExists(prefs_dir_.Append(kKey)));
+  EXPECT_FALSE(base::PathExists(prefs_dir_.Append(kKey)));
 }
 
 TEST_F(PrefsTest, SetInt64Max) {
   const char kKey[] = "test-max-int";
   EXPECT_TRUE(prefs_.SetInt64(kKey, kint64max));
   string value;
-  EXPECT_TRUE(file_util::ReadFileToString(prefs_dir_.Append(kKey), &value));
-  EXPECT_EQ(StringPrintf("%" PRIi64, kint64max), value);
+  EXPECT_TRUE(base::ReadFileToString(prefs_dir_.Append(kKey), &value));
+  EXPECT_EQ(base::StringPrintf("%" PRIi64, kint64max), value);
 }
 
 TEST_F(PrefsTest, SetInt64Min) {
   const char kKey[] = "test-min-int";
   EXPECT_TRUE(prefs_.SetInt64(kKey, kint64min));
   string value;
-  EXPECT_TRUE(file_util::ReadFileToString(prefs_dir_.Append(kKey), &value));
-  EXPECT_EQ(StringPrintf("%" PRIi64, kint64min), value);
+  EXPECT_TRUE(base::ReadFileToString(prefs_dir_.Append(kKey), &value));
+  EXPECT_EQ(base::StringPrintf("%" PRIi64, kint64min), value);
 }
 
 TEST_F(PrefsTest, GetBooleanFalse) {
@@ -226,7 +226,7 @@
   const char kKey[] = "test-bool";
   EXPECT_TRUE(prefs_.SetBoolean(kKey, true));
   string value;
-  EXPECT_TRUE(file_util::ReadFileToString(prefs_dir_.Append(kKey), &value));
+  EXPECT_TRUE(base::ReadFileToString(prefs_dir_.Append(kKey), &value));
   EXPECT_EQ("true", value);
 }
 
@@ -234,14 +234,14 @@
   const char kKey[] = "test-bool";
   EXPECT_TRUE(prefs_.SetBoolean(kKey, false));
   string value;
-  EXPECT_TRUE(file_util::ReadFileToString(prefs_dir_.Append(kKey), &value));
+  EXPECT_TRUE(base::ReadFileToString(prefs_dir_.Append(kKey), &value));
   EXPECT_EQ("false", value);
 }
 
 TEST_F(PrefsTest, SetBooleanBadKey) {
   const char kKey[] = "s p a c e s";
   EXPECT_FALSE(prefs_.SetBoolean(kKey, true));
-  EXPECT_FALSE(file_util::PathExists(prefs_dir_.Append(kKey)));
+  EXPECT_FALSE(base::PathExists(prefs_dir_.Append(kKey)));
 }
 
 TEST_F(PrefsTest, ExistsWorks) {