Remove OnRecordingDisabled() metrics client interface.

chrome/browser/metrics/metrics_reporting_state.cc

Index: chrome/browser/metrics/metrics_reporting_state.cc
diff --git a/chrome/browser/metrics/metrics_reporting_state.cc b/chrome/browser/metrics/metrics_reporting_state.cc
index 58f34f97938720ed7c1a65cc085d08fb7935b86f..962d37cc65f843cac7c59fbb088f86f84d965038 100644
--- a/chrome/browser/metrics/metrics_reporting_state.cc
+++ b/chrome/browser/metrics/metrics_reporting_state.cc
@@ -9,6 +9,7 @@
 #include "build/build_config.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/metrics/chrome_metrics_service_accessor.h"
+#include "chrome/common/crash_keys.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/installer/util/google_update_settings.h"
 #include "components/metrics/metrics_pref_names.h"
@@ -60,34 +61,16 @@ bool SetGoogleUpdateSettings(bool enabled) {
 void SetMetricsReporting(bool to_update_pref,
                          const OnMetricsReportingCallbackType& callback_fn,
                          bool updated_pref) {
-  metrics::MetricsService* metrics = g_browser_process->metrics_service();
-
 #if !defined(OS_ANDROID)
   g_browser_process->local_state()->SetBoolean(
       metrics::prefs::kMetricsReportingEnabled, updated_pref);
 #endif  // !defined(OS_ANDROID)
 
-  // Clear the client id pref when opting out. Note: Mirrors code in
-  // uma_session_stats.cc. TODO(asvitkine): Unify.
-  if (!updated_pref) {
-    // Note: Clearing client id will not affect the running state (e.g. field
-    // trial randomization), as the pref is only read on startup.
-    g_browser_process->local_state()->ClearPref(
-        metrics::prefs::kMetricsClientID);
-    g_browser_process->local_state()->ClearPref(
-        metrics::prefs::kMetricsReportingEnabledTimestamp);
-  }
+  UpdateMetricsPrefsOnPermissionChange(updated_pref);
 
   // Uses the current state of whether reporting is enabled to enable services.
   g_browser_process->GetMetricsServicesManager()->UpdateUploadPermissions(true);
 
-  // When a user opts in to the metrics reporting service, the previously
-  // collected data should be cleared to ensure that nothing is reported before
-  // a user opts in and all reported data is accurate.
-  // TODO(asvitkine): This logic should be added to uma_session_stats.cc too.
-  if (updated_pref && metrics)
-    metrics->ClearSavedStabilityMetrics();
-
   if (to_update_pref == updated_pref) {
     RecordMetricsReportingHistogramValue(updated_pref ?
         METRICS_REPORTING_ENABLED : METRICS_REPORTING_DISABLED);
@@ -138,6 +121,24 @@ void ChangeMetricsReportingStateWithReply(
       base::Bind(&SetMetricsReporting, enabled, callback_fn));
 }
 
+void UpdateMetricsPrefsOnPermissionChange(bool metrics_enabled) {

[jwd, 2016/08/16 20:30:04]

Didn't think to ask this in the last review, but this seems like this might
belong in the MetricsStateManager, at least the pref related stuff. Can anything
be moved there?

[Alexei Svitkine (slow), 2016/08/16 21:07:50]

It's definitely a good question. There's a couple of issues - one is that it's
hard to get a pointer the the MetricsStateManager from the two callers and
MetricsStateManager is inside the component which currently can't depend on
crash_keys to clear the crash id.

+  if (metrics_enabled) {
+    // When a user opts in to the metrics reporting service, the previously
+    // collected data should be cleared to ensure that nothing is reported
+    // before a user opts in and all reported data is accurate.
+    g_browser_process->metrics_service()->ClearSavedStabilityMetrics();
+  } else {
+    // Clear the client id pref when opting out.
+    // Note: Clearing client id will not affect the running state (e.g. field
+    // trial randomization), as the pref is only read on startup.
+    g_browser_process->local_state()->ClearPref(
+        metrics::prefs::kMetricsClientID);
+    g_browser_process->local_state()->ClearPref(
+        metrics::prefs::kMetricsReportingEnabledTimestamp);
+    crash_keys::ClearMetricsClientId();
+  }
+}
+
 bool IsMetricsReportingPolicyManaged() {
   const PrefService* pref_service = g_browser_process->local_state();
   const PrefService::Preference* pref =