Consolidates accessing and setting the UMA pref to be within metrics code

chrome/browser/metrics/metrics_reporting_state.h

Index: chrome/browser/metrics/metrics_reporting_state.h
diff --git a/chrome/browser/metrics/metrics_reporting_state.h b/chrome/browser/metrics/metrics_reporting_state.h
index c333d84e52b87cfbe39697c3be71c829659838a2..1647442ad77551b26f5f01780c67234dbb5fa826 100644
--- a/chrome/browser/metrics/metrics_reporting_state.h
+++ b/chrome/browser/metrics/metrics_reporting_state.h
@@ -5,12 +5,16 @@
 #ifndef CHROME_BROWSER_METRICS_METRICS_REPORTING_STATE_H_
 #define CHROME_BROWSER_METRICS_METRICS_REPORTING_STATE_H_
 
-// Tries to set crash stats upload consent to |enabled|. Regardless of success,
-// if crash stats uploading is enabled, starts the MetricsService; otherwise
-// stops it.
-// Returns whether crash stats uploading is enabled.
-// TODO(tfarina): This method is pretty confusing. Clean this up and rename it
-// to something that makes more sense.
-bool ResolveMetricsReportingEnabled(bool enabled);
+#include "base/callback.h"
+#include "components/metrics/metrics_service.h"
+
+
+// Initiates the necessary changes for MetricsReportingEnabled change on a
+// thread with IO access.

[Alexei Svitkine (slow), 2014/09/05 15:22:48]

Please document the params.

Also, please document which platforms this currently doesn't work on with a
TODO. (Android and CrOS)

[gayane -on leave until 09-2017, 2014/09/05 18:30:20]

Done.

+void InitiateMetricsReportingChange(bool enabled,
+                                    base::Callback<void(bool)> callback_fn);
+
+// Returns weather MetricsReporting can be modified by user.

[Alexei Svitkine (slow), 2014/09/05 15:22:48]

Nit: "by the user."

[gayane -on leave until 09-2017, 2014/09/05 18:30:20]

Done.

+bool IsMetricsReportingUserChangable();
 
 #endif  // CHROME_BROWSER_METRICS_METRICS_REPORTING_STATE_H_