More complete implementation for condition and log matchers in statsd.

+ also synced proto from google3 to fix the LogEntryMatcher proto

+ MetricsManager represents StatsdConfig, it's responsible for initializing and managing all
LogEntryMatcher, Condition, and Metrics. Start review from here.

+ Added more complete StatsdConfig initialization, including building the map for:
    LogEntryMatcher -> Metrics
    LogEntryMatcher -> Condition
    Condition       -> Metrics.

    All the maps use index(int). The extra amount of memory for storing mappings help us
    quickly process log events.

  The StatsdConfig initialization process detects malformed config
  - Circle dependency
  - Missing definition
  etc.

 And once we detect ANY error, statsd will reject the config. And the resources related to this
 config will be released.

Test: Added unit tests
Change-Id: I2c4aefdbf3e2aa1701eacbb2fb5e653819ec1fbb
diff --git a/cmds/statsd/src/matchers/SimpleLogMatchingTracker.cpp b/cmds/statsd/src/matchers/SimpleLogMatchingTracker.cpp
new file mode 100644
index 0000000..1c83039
--- /dev/null
+++ b/cmds/statsd/src/matchers/SimpleLogMatchingTracker.cpp
@@ -0,0 +1,75 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "SimpleLogMatchingTracker"
+#define DEBUG true  // STOPSHIP if true
+#define VLOG(...) \
+    if (DEBUG) ALOGD(__VA_ARGS__);
+
+#include "SimpleLogMatchingTracker.h"
+#include <cutils/log.h>
+#include <log/logprint.h>
+
+using std::string;
+using std::unique_ptr;
+using std::unordered_map;
+using std::vector;
+
+namespace android {
+namespace os {
+namespace statsd {
+
+SimpleLogMatchingTracker::SimpleLogMatchingTracker(const string& name, const int index,
+                                                   const SimpleLogEntryMatcher& matcher)
+    : LogMatchingTracker(name, index), mMatcher(matcher) {
+    for (int i = 0; i < matcher.tag_size(); i++) {
+        mTagIds.insert(matcher.tag(i));
+    }
+    mInitialized = true;
+}
+
+SimpleLogMatchingTracker::~SimpleLogMatchingTracker() {
+}
+
+bool SimpleLogMatchingTracker::init(const vector<LogEntryMatcher>& allLogMatchers,
+                                    const vector<sp<LogMatchingTracker>>& allTrackers,
+                                    const unordered_map<string, int>& matcherMap,
+                                    vector<bool>& stack) {
+    // no need to do anything.
+    return true;
+}
+
+void SimpleLogMatchingTracker::onLogEvent(const LogEventWrapper& event,
+                                          const vector<sp<LogMatchingTracker>>& allTrackers,
+                                          vector<MatchingState>& matcherResults) {
+    if (matcherResults[mIndex] != MatchingState::kNotComputed) {
+        VLOG("Matcher %s already evaluated ", mName.c_str());
+        return;
+    }
+
+    if (mTagIds.find(event.tagId) == mTagIds.end()) {
+        matcherResults[mIndex] = MatchingState::kNotMatched;
+        return;
+    }
+
+    bool matched = matchesSimple(mMatcher, event);
+    matcherResults[mIndex] = matched ? MatchingState::kMatched : MatchingState::kNotMatched;
+    VLOG("Stats SimpleLogMatcher %s matched? %d", mName.c_str(), matched);
+}
+
+}  // namespace statsd
+}  // namespace os
+}  // namespace android