ExternalDataUseObserver JNI integration

chrome/browser/android/data_usage/external_data_use_observer.h

Index: chrome/browser/android/data_usage/external_data_use_observer.h
diff --git a/chrome/browser/android/data_usage/external_data_use_observer.h b/chrome/browser/android/data_usage/external_data_use_observer.h
index 1db5416a40cdb7b20bd6ed14c9f2933d43ea67cc..f0fdb6cbfbceac79991ad2a2089869238bf28987 100644
--- a/chrome/browser/android/data_usage/external_data_use_observer.h
+++ b/chrome/browser/android/data_usage/external_data_use_observer.h
@@ -80,6 +80,9 @@ class ExternalDataUseObserver : public data_usage::DataUseAggregator::Observer {
   // called on UI thread.
   void OnReportDataUseDone(JNIEnv* env, jobject obj, bool success);
 
+  // Returns the external data use observer field trial name.
+  const std::string GetExternalDataUseObserverFieldTrialName() const;

[sclittle, 2015/11/06 23:42:50]

Make this a static constant.

[tbansal1, 2015/11/07 01:32:43]

This function would be used by Raj to control other params in his classes (e.g.,
how many tabs to maintain the memory etc.)

[sclittle, 2015/11/07 02:05:32]

Could it just be a publicly visible static constant then?

[tbansal1, 2015/11/07 02:33:02]

Done.

+
  private:
   FRIEND_TEST_ALL_PREFIXES(ExternalDataUseObserverTest, SingleRegex);
   FRIEND_TEST_ALL_PREFIXES(ExternalDataUseObserverTest, TwoRegex);
@@ -93,6 +96,10 @@ class ExternalDataUseObserver : public data_usage::DataUseAggregator::Observer {
                            TimestampsMergedCorrectly);
   FRIEND_TEST_ALL_PREFIXES(ExternalDataUseObserverTest, HashFunction);
   FRIEND_TEST_ALL_PREFIXES(ExternalDataUseObserverTest, BufferSize);
+  FRIEND_TEST_ALL_PREFIXES(ExternalDataUseObserverTest,
+                           PeriodicFetchMatchingRules);
+  FRIEND_TEST_ALL_PREFIXES(ExternalDataUseObserverTest, BufferDataUseReports);
+  FRIEND_TEST_ALL_PREFIXES(ExternalDataUseObserverTest, Variations);
 
   // DataUseReportKey is a unique identifier for a data use report.
   struct DataUseReportKey {
@@ -214,6 +221,9 @@ class ExternalDataUseObserver : public data_usage::DataUseAggregator::Observer {
   // size |kMaxBufferSize|, then the oldest entry will be removed.
   static const size_t kMaxBufferSize = 100;
 
+  // Populates various parameters from the values specified in the field trial.
+  void PopulateFieldTrialParams();

[sclittle, 2015/11/06 23:42:50]

Could this just be a few anonymous functions in the .cc file instead of a
method?

[tbansal1, 2015/11/07 01:32:43]

Done.

+
   // Creates Java object. Must be called on the UI thread.
   void CreateJavaObjectOnUIThread();
 
@@ -312,6 +322,20 @@ class ExternalDataUseObserver : public data_usage::DataUseAggregator::Observer {
   // Time when the data use reports were last received from DataUseAggregator.
   base::Time previous_report_time_;
 
+  // Time when the matching rules were last fetched.
+  base::TimeTicks last_matching_rules_fetch_time_;
+
+  // Total number of bytes transmitted or received across all the buffered
+  // reports.
+  int64_t total_bytes_buffered_;
+
+  // Duration after which matching rules are periodically fetched.
+  base::TimeDelta fetch_matching_rules_duration_;
+
+  // Minimum number of bytes that should be buffered before a data use report is
+  // submitted.
+  int64_t data_use_report_min_bytes_;
+
   base::ThreadChecker thread_checker_;
 
   // |io_weak_factory_| and |ui_weak_factory_| are used for posting tasks on the