Magnifier: Prevent useless operation in enabling/disabling magnifier.

chrome/browser/chromeos/chrome_browser_main_chromeos.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.
 
 #include "chrome/browser/chromeos/chrome_browser_main_chromeos.h"
 
 #include <string>
 #include <vector>
 
 #include "ash/shell.h"
@@ skipping 419 matching lines @@
   // TODO(abarth): Should this move to InitializeNetworkOptions()?
   // Allow access to file:// on ChromeOS for tests.
   if (parsed_command_line().HasSwitch(::switches::kAllowFileAccess))
     ChromeNetworkDelegate::AllowAccessToAllFiles();
 
   if (parsed_command_line().HasSwitch(::switches::kEnableContacts)) {
     contact_manager_.reset(new contacts::ContactManager());
     contact_manager_->Init();
   }
 
+  // Initialize magnification manager before ash tray is created.
+  chromeos::MagnificationManager::Initialize();
+
   // There are two use cases for kLoginUser:
   //   1) if passed in tandem with kLoginPassword, to drive a "StubLogin"
   //   2) if passed alone, to signal that the indicated user has already
   //      logged in and we should behave accordingly.
   // This handles case 2.
   if (parsed_command_line().HasSwitch(::switches::kLoginUser) &&
       !parsed_command_line().HasSwitch(::switches::kLoginPassword)) {
     std::string username =
         parsed_command_line().GetSwitchValueASCII(::switches::kLoginUser);
     VLOG(1) << "Relaunching browser for user: " << username;
@@ skipping 70 matching lines @@
   // Initialize the brightness observer so that we'll display an onscreen
   // indication of brightness changes during login.
   brightness_observer_.reset(new BrightnessObserver());
   output_observer_.reset(new OutputObserver());
   resume_observer_.reset(new ResumeObserver());
   screen_lock_observer_.reset(new ScreenLockObserver());
   if (KioskModeSettings::Get()->IsKioskModeEnabled()) {
     power_state_override_ = new PowerStateOverride(
         PowerStateOverride::BLOCK_DISPLAY_SLEEP);
   }
-  magnification_manager_.reset(
-      chromeos::MagnificationManager::CreateInstance());
   chromeos::accessibility::Initialize();
 
   primary_display_switch_observer_.reset(
       new PrimaryDisplaySwitchObserver());
 
   removable_device_notifications_ =
       new RemovableDeviceNotificationsCros();
 
   // Initialize the network portal detector for Chrome OS. The network
   // portal detector starts to listen for notifications from
@@ skipping 78 matching lines @@
 
   // Tell DeviceSettingsService to stop talking to session_manager.
   DeviceSettingsService::Get()->Shutdown();
 
   // We should remove observers attached to D-Bus clients before
   // DBusThreadManager is shut down.
   screen_lock_observer_.reset();
   resume_observer_.reset();
   brightness_observer_.reset();
   output_observer_.reset();
-  magnification_manager_.reset();
   power_state_override_ = NULL;
 
   // The XInput2 event listener needs to be shut down earlier than when
   // Singletons are finally destroyed in AtExitManager.
   XInputHierarchyChangedEventListener::GetInstance()->Stop();
 
   // chromeos::SystemKeyEventListener::Shutdown() is always safe to call,
   // even if Initialize() wasn't called.
   SystemKeyEventListener::Shutdown();
   imageburner::BurnManager::Shutdown();
   AudioHandler::Shutdown();
 
   WebSocketProxyController::Shutdown();
 
   // Let classes unregister themselves as observers of the ash::Shell singleton
   // before the shell is destroyed.
   user_activity_notifier_.reset();
   video_activity_notifier_.reset();
   primary_display_switch_observer_.reset();
 
   // Detach D-Bus clients before DBusThreadManager is shut down.
   power_button_observer_.reset();
   screen_dimming_observer_.reset();
 
   // Delete ContactManager while |g_browser_process| is still alive.
   contact_manager_.reset();
 
+  chromeos::MagnificationManager::Shutdown();
+
   ChromeBrowserMainPartsLinux::PostMainMessageLoopRun();
 }
 
 void ChromeBrowserMainPartsChromeos::SetupPlatformFieldTrials() {
   SetupLowMemoryHeadroomFieldTrial();
 }
 
 void ChromeBrowserMainPartsChromeos::SetupLowMemoryHeadroomFieldTrial() {
   chrome::VersionInfo::Channel channel = chrome::VersionInfo::GetChannel();
   // Only enable this experiment on Canary and Dev, since it's possible
@@ skipping 34 matching lines @@
     } else if (trial->group() == margin_200mb) {
       LOG(WARNING) << "low_mem: Part of '200MB' experiment";
       LowMemoryObserver::SetLowMemoryMargin(200);
     } else {
       LOG(WARNING) << "low_mem: Part of 'default' experiment";
     }
   }
 }
 
 }  //  namespace chromeos