Additional tracing and histogram in Extensions startup.

chrome/browser/extensions/extension_service.cc

 // Copyright (c) 2013 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/extensions/extension_service.h"
 
 #include <algorithm>
 #include <iterator>
 #include <set>
 
@@ skipping 258 matching lines @@
       install_updates_when_idle_(true),
       ready_(ready),
       update_once_all_providers_are_ready_(false),
       browser_terminating_(false),
       installs_delayed_for_gc_(false),
       is_first_run_(false),
       block_extensions_(false),
       shared_module_service_(new extensions::SharedModuleService(profile_)),
       app_data_migrator_(new extensions::AppDataMigrator(profile_, registry_)) {
   CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  TRACE_EVENT0("browser,startup", "ExtensionService::ExtensionService::ctor");
 
   // Figure out if extension installation should be enabled.
   if (extensions::ExtensionsBrowserClient::Get()->AreExtensionsDisabled(
           *command_line, profile))
     extensions_enabled_ = false;
 
   registrar_.Add(this, chrome::NOTIFICATION_APP_TERMINATING,
                  content::NotificationService::AllBrowserContextsAndSources());
   registrar_.Add(this,
                  extensions::NOTIFICATION_EXTENSION_PROCESS_TERMINATED,
                  content::NotificationService::AllBrowserContextsAndSources());
   registrar_.Add(this, content::NOTIFICATION_RENDERER_PROCESS_TERMINATED,
                  content::NotificationService::AllBrowserContextsAndSources());
   registrar_.Add(this, chrome::NOTIFICATION_UPGRADE_RECOMMENDED,
                  content::NotificationService::AllBrowserContextsAndSources());
   registrar_.Add(this,
                  chrome::NOTIFICATION_PROFILE_DESTRUCTION_STARTED,
                  content::Source<Profile>(profile_));
 
   extensions::ExtensionManagementFactory::GetForBrowserContext(profile_)
       ->AddObserver(this);
 
-  // Set up the ExtensionUpdater
+  // Set up the ExtensionUpdater.
   if (autoupdate_enabled) {
     int update_frequency = extensions::kDefaultUpdateFrequencySeconds;
     if (command_line->HasSwitch(switches::kExtensionsUpdateFrequency)) {
       base::StringToInt(command_line->GetSwitchValueASCII(
           switches::kExtensionsUpdateFrequency),
           &update_frequency);
     }
     updater_.reset(new extensions::ExtensionUpdater(
         this,
         extension_prefs,
@@ skipping 2244 matching lines @@
 }
 
 void ExtensionService::OnProfileDestructionStarted() {
   ExtensionIdSet ids_to_unload = registry_->enabled_extensions().GetIDs();
   for (ExtensionIdSet::iterator it = ids_to_unload.begin();
        it != ids_to_unload.end();
        ++it) {
     UnloadExtension(*it, UnloadedExtensionInfo::REASON_PROFILE_SHUTDOWN);
   }
 }