Magnifier: Prevent useless operation in enabling/disabling magnifier.

chrome/browser/chromeos/chrome_browser_main_chromeos.cc

Index: chrome/browser/chromeos/chrome_browser_main_chromeos.cc
diff --git a/chrome/browser/chromeos/chrome_browser_main_chromeos.cc b/chrome/browser/chromeos/chrome_browser_main_chromeos.cc
index fcbddc3ea35630369ac1ec2f63475185ffae85b2..c1565e83e98a038c2f8685b9712cbac308b8980e 100644
--- a/chrome/browser/chromeos/chrome_browser_main_chromeos.cc
+++ b/chrome/browser/chromeos/chrome_browser_main_chromeos.cc
@@ -437,6 +437,9 @@ void ChromeBrowserMainPartsChromeos::PreProfileInit() {
     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
@@ -527,8 +530,6 @@ void ChromeBrowserMainPartsChromeos::PostProfileInit() {
     power_state_override_ = new PowerStateOverride(
         PowerStateOverride::BLOCK_DISPLAY_SLEEP);
   }
-  magnification_manager_.reset(
-      chromeos::MagnificationManager::CreateInstance());
   chromeos::accessibility::Initialize();
 
   primary_display_switch_observer_.reset(
@@ -627,7 +628,6 @@ void ChromeBrowserMainPartsChromeos::PostMainMessageLoopRun() {
   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
@@ -655,6 +655,8 @@ void ChromeBrowserMainPartsChromeos::PostMainMessageLoopRun() {
   // Delete ContactManager while |g_browser_process| is still alive.
   contact_manager_.reset();
 
+  chromeos::MagnificationManager::Shutdown();
+
   ChromeBrowserMainPartsLinux::PostMainMessageLoopRun();
 }