Log operator code histogram on new metric log

chrome/browser/metrics/metrics_service.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 //------------------------------------------------------------------------------
 // Description of the life cycle of a instance of MetricsService.
 //
 //  OVERVIEW
 //
 // A MetricsService instance is typically created at application startup.  It is
@@ skipping 1026 matching lines @@
     const tracked_objects::ProcessDataSnapshot& process_data,
     int process_type) {
   DCHECK_EQ(INIT_TASK_SCHEDULED, state_);
 
   // Upon the first callback, create the initial log so that we can immediately
   // save the profiler data.
   if (!initial_metrics_log_.get()) {
     initial_metrics_log_.reset(
         new MetricsLog(state_manager_->client_id(), session_id_,
                        MetricsLog::ONGOING_LOG));
+    NotifyOnDidCreateMetricsLog();
   }
 
   initial_metrics_log_->RecordProfilerData(process_data, process_type);
 }
 
 void MetricsService::FinishedReceivingProfilerData() {
   DCHECK_EQ(INIT_TASK_SCHEDULED, state_);
   state_ = INIT_TASK_DONE;
   scheduler_->InitTaskComplete();
 }
@@ skipping 13 matching lines @@
   last_updated_time_ = now;
 
   const int64 incremental_time_secs = incremental_uptime->InSeconds();
   if (incremental_time_secs > 0) {
     int64 metrics_uptime = pref->GetInt64(prefs::kUninstallMetricsUptimeSec);
     metrics_uptime += incremental_time_secs;
     pref->SetInt64(prefs::kUninstallMetricsUptimeSec, metrics_uptime);
   }
 }
 
+void MetricsService::AddObserver(MetricsServiceObserver* observer) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  observers_.AddObserver(observer);
+}
+
+void MetricsService::RemoveObserver(MetricsServiceObserver* observer) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  observers_.RemoveObserver(observer);
+}
+
+void MetricsService::NotifyOnDidCreateMetricsLog() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  FOR_EACH_OBSERVER(
+      MetricsServiceObserver, observers_, OnDidCreateMetricsLog());
+}
+
 //------------------------------------------------------------------------------
 // State save methods
 
 void MetricsService::ScheduleNextStateSave() {
   state_saver_factory_.InvalidateWeakPtrs();
 
   base::MessageLoop::current()->PostDelayedTask(FROM_HERE,
       base::Bind(&MetricsService::SaveLocalState,
                  state_saver_factory_.GetWeakPtr()),
       base::TimeDelta::FromMinutes(kSaveStateIntervalMinutes));
@@ skipping 15 matching lines @@
 
 //------------------------------------------------------------------------------
 // Recording control methods
 
 void MetricsService::OpenNewLog() {
   DCHECK(!log_manager_.current_log());
 
   log_manager_.BeginLoggingWithLog(
       new MetricsLog(state_manager_->client_id(), session_id_,
                      MetricsLog::ONGOING_LOG));
+  NotifyOnDidCreateMetricsLog();
   if (state_ == INITIALIZED) {
     // We only need to schedule that run once.
     state_ = INIT_TASK_SCHEDULED;
 
     // Schedules a task on the file thread for execution of slower
     // initialization steps (such as plugin list generation) necessary
     // for sending the initial log.  This avoids blocking the main UI
     // thread.
     BrowserThread::PostDelayedTask(
         BrowserThread::FILE,
@@ skipping 277 matching lines @@
 }
 
 void MetricsService::PrepareInitialStabilityLog() {
   DCHECK_EQ(INITIALIZED, state_);
   PrefService* pref = g_browser_process->local_state();
   DCHECK_NE(0, pref->GetInteger(prefs::kStabilityCrashCount));
 
   scoped_ptr<MetricsLog> initial_stability_log(
       new MetricsLog(state_manager_->client_id(), session_id_,
                      MetricsLog::INITIAL_STABILITY_LOG));
+  NotifyOnDidCreateMetricsLog();

[Alexei Svitkine (slow), 2014/05/08 21:00:56]

Remove this line. Possibly replace with a comment.

It's not correct to do this here, since the stability log describes stats from
the _previous_ session (and generally has almost no histograms except for very
specific ones that also describe stats about the previous session). The next
line loads the previously saved system profile from then.

So it's not correct to record these stats there.

[bolian, 2014/05/08 22:17:57]

Done.

   if (!initial_stability_log->LoadSavedEnvironmentFromPrefs())
     return;
   initial_stability_log->RecordStabilityMetrics(base::TimeDelta(),
                                                 base::TimeDelta());
   log_manager_.LoadPersistedUnsentLogs();
 
   log_manager_.PauseCurrentLog();
   log_manager_.BeginLoggingWithLog(initial_stability_log.release());
 #if defined(OS_ANDROID)
   ConvertAndroidStabilityPrefsToHistograms(pref);
@@ skipping 509 matching lines @@
   // Android has its own settings for metrics / crash uploading.
   const PrefService* prefs = g_browser_process->local_state();
   return prefs->GetBoolean(prefs::kCrashReportingEnabled);
 #else
   return MetricsServiceHelper::IsMetricsReportingEnabled();
 #endif
 #else
   return false;
 #endif
 }
+
+void MetricsServiceHelper::AddMetricsServiceObserver(
+    MetricsServiceObserver* observer) {
+  MetricsService* metrics_service = g_browser_process->metrics_service();
+  if (metrics_service)
+    metrics_service->AddObserver(observer);
+}
+
+void MetricsServiceHelper::RemoveMetricsServiceObserver(
+    MetricsServiceObserver* observer) {
+  MetricsService* metrics_service = g_browser_process->metrics_service();
+  if (metrics_service)
+    metrics_service->RemoveObserver(observer);
+}