Refactor HashedExtensionMetrics into ExtensionsMetricsProvider.

chrome/browser/metrics/metrics_log.cc

Index: chrome/browser/metrics/metrics_log.cc
diff --git a/chrome/browser/metrics/metrics_log.cc b/chrome/browser/metrics/metrics_log.cc
index 1769522598b0c8620553e94c30d88b5cc35ca59c..8392840a726f59f552783a154fa920bae4a15175 100644
--- a/chrome/browser/metrics/metrics_log.cc
+++ b/chrome/browser/metrics/metrics_log.cc
@@ -31,7 +31,6 @@
 #include "chrome/browser/autocomplete/autocomplete_result.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/google/google_util.h"
-#include "chrome/browser/metrics/extension_metrics.h"
 #include "chrome/browser/omnibox/omnibox_log.h"
 #include "chrome/browser/plugins/plugin_prefs.h"
 #include "chrome/browser/profiles/profile_manager.h"
@@ -404,10 +403,11 @@ static base::LazyInstance<std::string>::Leaky
 MetricsLog::MetricsLog(const std::string& client_id,
                        int session_id,
                        LogType log_type)
-    : MetricsLogBase(client_id, session_id, log_type,
+    : MetricsLogBase(client_id,
+                     session_id,
+                     log_type,
                      MetricsLog::GetVersionString()),
-      creation_time_(base::TimeTicks::Now()),
-      extension_metrics_(uma_proto()->client_id()) {
+      creation_time_(base::TimeTicks::Now()) {
   uma_proto()->mutable_system_profile()->set_channel(
       AsProtobufChannel(chrome::VersionInfo::GetChannel()));
 
@@ -797,7 +797,6 @@ void MetricsLog::RecordEnvironment(
   WriteGoogleUpdateProto(google_update_metrics);
 
   WritePluginList(plugin_list);
-  extension_metrics_.WriteExtensionList(uma_proto()->mutable_system_profile());
 
   std::vector<ActiveGroupId> field_trial_ids;
   GetFieldTrialIds(&field_trial_ids);