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..2f486b0f022fa86bda6d84267cfcd5ad3445f2b5 100644
--- a/chrome/browser/metrics/metrics_reporting_state.h
+++ b/chrome/browser/metrics/metrics_reporting_state.h
@@ -5,12 +5,20 @@
 #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. The parameter |enabled| indicates whether
+// MetricsReportingEnabled should be true or false and |callback_fn| is a

[Alexei Svitkine (slow), 2014/09/05 20:50:25]

How about this wording which also talks about metrics service:

// Initiates a change to metrics reporting state to the new value of |enabled|.
// Starts or stops the metrics service based on the new state and then runs
// |callback_fn| (which can be null) with the updated state (as the operation
// may fail). On platforms other than CrOS and Android, also updates the
// underlying pref.
// TODO(gayane): Support setting the pref on all platforms.

[gayane -on leave until 09-2017, 2014/09/08 18:32:46]

Done.

On 2014/09/05 20:50:25, Alexei Svitkine wrote:

+// reference to a callback function which will be called with a success status.
+// |callback_fn| can be null.
+// TODO(gayane) Currently this function doesn't change the preference for CrOS.

[Alexei Svitkine (slow), 2014/09/05 20:50:25]

Mention that it doesn't support Android either. (But this is OK since Android
doesn't call this since it has its own settings page.)

Also, add a : after the TODO(gayane)

(This is addressed in my suggestion above for the wording.)

[gayane -on leave until 09-2017, 2014/09/08 18:32:46]

Acknowledged.

+void InitiateMetricsReportingChange(bool enabled,
+                                    base::Callback<void(bool)> callback_fn);
+
+// Returns whether MetricsReporting can be modified by the user.
+bool IsMetricsReportingUserChangable();
 
 #endif  // CHROME_BROWSER_METRICS_METRICS_REPORTING_STATE_H_