Create and pass shared-histogram-allocator from browser to renderer.

chrome/browser/metrics/chrome_metrics_service_client.cc

 // Copyright 2014 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.
 
 #include "chrome/browser/metrics/chrome_metrics_service_client.h"
 
 #include <stddef.h>
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "base/path_service.h"
 #include "base/rand_util.h"
 #include "base/strings/string16.h"
 #include "base/threading/platform_thread.h"
 #include "build/build_config.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/google/google_brand.h"
 #include "chrome/browser/metrics/chrome_stability_metrics_provider.h"
 #include "chrome/browser/metrics/metrics_reporting_state.h"
+#include "chrome/browser/metrics/subprocess_metrics_provider.h"
 #include "chrome/browser/metrics/time_ticks_experiment_win.h"
 #include "chrome/browser/sync/chrome_sync_client.h"
 #include "chrome/browser/ui/browser_otr_state.h"
 #include "chrome/common/channel_info.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/crash_keys.h"
 #include "chrome/common/features.h"
 #include "chrome/installer/util/util_constants.h"
@@ skipping 313 matching lines @@
   // metrics service so that metrics log manager is initialized correctly.
   if (ShouldClearSavedMetrics()) {
     PrefService* local_state = g_browser_process->local_state();
     local_state->ClearPref(metrics::prefs::kMetricsInitialLogs);
     local_state->ClearPref(metrics::prefs::kMetricsOngoingLogs);
   }
 
   metrics_service_.reset(new metrics::MetricsService(
       metrics_state_manager_, this, g_browser_process->local_state()));
 
+  // Gets access to persistent metrics shared by sub-processes.
+  metrics_service_->RegisterMetricsProvider(
+      scoped_ptr<metrics::MetricsProvider>(new SubprocessMetricsProvider()));
+
   // Register metrics providers.
 #if defined(ENABLE_EXTENSIONS)
   metrics_service_->RegisterMetricsProvider(
       scoped_ptr<metrics::MetricsProvider>(
           new ExtensionsMetricsProvider(metrics_state_manager_)));
 #endif
   metrics_service_->RegisterMetricsProvider(
       scoped_ptr<metrics::MetricsProvider>(new metrics::NetworkMetricsProvider(
           content::BrowserThread::GetBlockingPool())));
 
@@ skipping 71 matching lines @@
 #if !defined(OS_CHROMEOS)
   metrics_service_->RegisterMetricsProvider(
       scoped_ptr<metrics::MetricsProvider>(
           SigninStatusMetricsProvider::CreateInstance(
               make_scoped_ptr(new ChromeSigninStatusMetricsProviderDelegate))));
 #endif  // !defined(OS_CHROMEOS)
 
   metrics_service_->RegisterMetricsProvider(
       scoped_ptr<metrics::MetricsProvider>(
           new sync_driver::DeviceCountMetricsProvider(base::Bind(
               &browser_sync::ChromeSyncClient::GetDeviceInfoTrackers))));

[Alexei Svitkine (slow), 2016/03/29 17:51:24]

In the future, please upload separate patchsets for rebases & addressing
comments. Otherwise, when I look at diffs between patchsets, I will see
unrelated changes as a result of the rebase. Thanks!

[bcwhite, 2016/03/30 21:25:55]

Acknowledged.

 
   // Clear stability metrics if it is the first time cellular upload logic
   // should apply to avoid sudden bulk uploads. It needs to be done after all
   // providers are registered.
   if (ShouldClearSavedMetrics())
     metrics_service_->ClearSavedStabilityMetrics();
 }
 
 void ChromeMetricsServiceClient::OnInitTaskGotHardwareClass() {
   const base::Closure got_bluetooth_adapter_callback =
@@ skipping 215 matching lines @@
       break;
 
     default:
       NOTREACHED();
   }
 }
 
 void ChromeMetricsServiceClient::OnURLOpenedFromOmnibox(OmniboxLog* log) {
   metrics_service_->OnApplicationNotIdle();
 }