histogram synchronizer code between renderer and browser for UMA and about_histogram

chrome/browser/browser_main.cc

 // Copyright (c) 2006-2008 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 "build/build_config.h"
 
 #include <algorithm>
 
 #include "app/resource_bundle.h"
 #include "base/command_line.h"
@@ skipping 22 matching lines @@
 #include "chrome/browser/metrics/metrics_service.h"
 #include "chrome/browser/net/dns_global.h"
 #include "chrome/browser/plugin_service.h"
 #include "chrome/browser/process_singleton.h"
 #include "chrome/browser/profile_manager.h"
 #include "chrome/browser/shell_integration.h"
 #include "chrome/browser/user_data_manager.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_switches.h"
+#include "chrome/common/histogram_synchronizer.h"
 #include "chrome/common/jstemplate_builder.h"
 #include "chrome/common/l10n_util.h"
 #include "chrome/common/main_function_params.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/pref_service.h"
 #include "chrome/common/result_codes.h"
 #include "grit/chromium_strings.h"
 #include "grit/generated_resources.h"
 #include "grit/net_resources.h"
 #include "net/base/net_module.h"
@@ skipping 280 matching lines @@
   if (!parsed_command_line.HasSwitch(switches::kNoErrorDialogs)) {
     // Display a warning if the user is running windows 2000.
     // TODO(port): We should probably change this to a "check for minimum
     // requirements" function, implemented by each platform.
     CheckForWin2000();
   }
 
   // Initialize histogram statistics gathering system.
   StatisticsRecorder statistics;
 
+  // Initialize histogram synchronizer system. This is a singleton and is used
+  // for posting tasks via NewRunnableMethod. Its deleted when it goes out of
+  // scope. Even though NewRunnableMethod does AddRef and Release, the object
+  // will not be deleted after the Task is executed.
+  scoped_refptr<HistogramSynchronizer> histogram_synchronizer =
+      new HistogramSynchronizer();
+
   // Initialize the shared instance of user data manager.
   scoped_ptr<UserDataManager> user_data_manager(UserDataManager::Create());
 
   // Try to create/load the profile.
   ProfileManager* profile_manager = browser_process->profile_manager();
   Profile* profile = profile_manager->GetDefaultProfile(user_data_dir);
   if (!profile) {
 #if defined(OS_WIN)
     user_data_dir = FilePath::FromWStringHack(
         UserDataDirDialog::RunUserDataDirDialog(user_data_dir.ToWStringHack()));
@@ skipping 274 matching lines @@
   if (metrics)
     metrics->Stop();
 
   // browser_shutdown takes care of deleting browser_process, so we need to
   // release it.
   browser_process.release();
   browser_shutdown::Shutdown();
 
   return result_code;
 }