Enabled client side sampling for user metrics reporting.

chrome/browser/metrics/chrome_metrics_service_accessor.h

 // 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.
 
 #ifndef CHROME_BROWSER_METRICS_CHROME_METRICS_SERVICE_ACCESSOR_H_
 #define CHROME_BROWSER_METRICS_CHROME_METRICS_SERVICE_ACCESSOR_H_
 
 #include <stdint.h>
 #include <string>
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "chrome/browser/metrics/metrics_reporting_state.h"
 #include "components/metrics/metrics_service_accessor.h"
 
 class BrowserProcessImpl;
 class Profile;
+class ChromeMetricsServiceClient;
 
 namespace {
 class CrashesDOMHandler;
 class FlashDOMHandler;
 }
 
 namespace chrome {
 void AttemptRestart();
 }
 
@@ skipping 64 matching lines @@
   friend class safe_browsing::IncidentReportingService;
   friend class speech::ChromeSpeechRecognitionManagerDelegate;
   friend class StackSamplingConfiguration;
   friend class system_logs::ChromeInternalLogSource;
   friend class UmaSessionStats;
   friend class safe_browsing::SRTFetcher;
   friend class safe_browsing::DownloadSBClient;
   friend class safe_browsing::SafeBrowsingService;
   friend class safe_browsing::SafeBrowsingUIManager;
   friend void SyzyASANRegisterExperiment(const char*, const char*);
+  friend class ChromeMetricsServiceClient;
 
   FRIEND_TEST_ALL_PREFIXES(ChromeMetricsServiceAccessorTest,
                            MetricsReportingEnabled);
 
   // Returns true if metrics reporting is enabled.
   // TODO(gayane): Consolidate metric prefs on all platforms.
   // http://crbug.com/362192,  http://crbug.com/532084
   static bool IsMetricsAndCrashReportingEnabled();
 
   // Calls metrics::MetricsServiceAccessor::RegisterSyntheticFieldTrial() with
   // g_browser_process->metrics_service(). See that function's declaration for
   // details.
   static bool RegisterSyntheticFieldTrial(const std::string& trial_name,
                                           const std::string& group_name);
 
   // Calls
   // metrics::MetricsServiceAccessor::RegisterSyntheticFieldTrialWithNameHash()
   // with g_browser_process->metrics_service(). See that function's declaration
   // for details.
   static bool RegisterSyntheticFieldTrialWithNameHash(
       uint32_t trial_name_hash,
       const std::string& group_name);
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(ChromeMetricsServiceAccessor);
 };
 
 #endif  // CHROME_BROWSER_METRICS_CHROME_METRICS_SERVICE_ACCESSOR_H_