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..57f82c496c6e98d56027169164d775d5d676bcb9 100644
--- a/chrome/browser/android/data_usage/external_data_use_observer.h
+++ b/chrome/browser/android/data_usage/external_data_use_observer.h
@@ -9,11 +9,11 @@
 #include <stdint.h>
 
 #include <string>
-#include <unordered_map>
 #include <vector>
 
 #include "base/android/jni_array.h"
 #include "base/android/scoped_java_ref.h"
+#include "base/containers/hash_tables.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.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;
+
  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 {
@@ -182,9 +189,8 @@ class ExternalDataUseObserver : public data_usage::DataUseAggregator::Observer {
     }
   };
 
-  typedef std::unordered_map<DataUseReportKey,
-                             DataUseReport,
-                             DataUseReportKeyHash> DataUseReports;
+  typedef base::hash_map<DataUseReportKey, DataUseReport, DataUseReportKeyHash>
+      DataUseReports;
 
   // Stores the matching rules.
   class MatchingRule {
@@ -312,6 +318,20 @@ 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.
+  const base::TimeDelta fetch_matching_rules_duration_;
+
+  // Minimum number of bytes that should be buffered before a data use report is
+  // submitted.
+  const 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