Moves AcceleratorController from Shell to WmShell

ash/wm/power_button_controller.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 "ash/wm/power_button_controller.h"
 
 #include "ash/common/accelerators/accelerator_controller.h"
 #include "ash/common/ash_switches.h"
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/shell_window_ids.h"
@@ skipping 62 matching lines @@
   // Avoid starting the lock/shutdown sequence if the power button is pressed
   // while the screen is off (http://crbug.com/128451), unless an external
   // display is still on (http://crosbug.com/p/24912).
   if (brightness_is_zero_ && !internal_display_off_and_external_display_on_)
     return;
 
   if (volume_down_pressed_ && down &&
       WmShell::Get()
           ->maximize_mode_controller()
           ->IsMaximizeModeWindowManagerEnabled()) {
-    Shell::GetInstance()->accelerator_controller()->PerformActionIfEnabled(
+    WmShell::Get()->accelerator_controller()->PerformActionIfEnabled(
         TAKE_SCREENSHOT);
     return;
   }
 
   const SessionStateDelegate* session_state_delegate =
       WmShell::Get()->GetSessionStateDelegate();
   if (has_legacy_power_button_) {
     // If power button releases won't get reported correctly because we're not
     // running on official hardware, just lock the screen or shut down
     // immediately.
@@ skipping 79 matching lines @@
 }
 
 void PowerButtonController::PowerButtonEventReceived(
     bool down,
     const base::TimeTicks& timestamp) {
   OnPowerButtonEvent(down, timestamp);
 }
 #endif  // defined(OS_CHROMEOS)
 
 }  // namespace ash