Refactor HashedExtensionMetrics into ExtensionsMetricsProvider.

chrome/browser/metrics/metrics_log.h

Index: chrome/browser/metrics/metrics_log.h
diff --git a/chrome/browser/metrics/metrics_log.h b/chrome/browser/metrics/metrics_log.h
index 46db78064b9e2ba238b44c6efe02b669883ad0d7..72bfff815aae2ad3ef054ce37bcc699fe8d2f441 100644
--- a/chrome/browser/metrics/metrics_log.h
+++ b/chrome/browser/metrics/metrics_log.h
@@ -12,14 +12,13 @@
 #include <vector>
 
 #include "base/basictypes.h"
-#include "chrome/browser/metrics/extension_metrics.h"
+#include "chrome/browser/metrics/extensions_metrics_provider.h"
 #include "chrome/browser/metrics/metrics_network_observer.h"
 #include "chrome/common/metrics/variations/variations_util.h"
 #include "chrome/installer/util/google_update_settings.h"
 #include "components/metrics/metrics_log_base.h"
 #include "ui/gfx/size.h"
 
-class HashedExtensionMetrics;
 class MetricsNetworkObserver;
 struct OmniboxLog;
 class PrefService;
@@ -199,9 +198,6 @@ class MetricsLog : public metrics::MetricsLogBase {
   // The time when the current log was created.
   const base::TimeTicks creation_time_;
 
-  // For including information on which extensions are installed in reports.
-  HashedExtensionMetrics extension_metrics_;
-
   DISALLOW_COPY_AND_ASSIGN(MetricsLog);
 };