Enable user change background image in settings page in Aura build.

ash/accelerators/accelerator_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/accelerators/accelerator_controller.h"
 
 #include "ash/accelerators/accelerator_table.h"
+#include "ash/desktop_background/desktop_background_controller.h"
 #include "ash/ash_switches.h"
 #include "ash/caps_lock_delegate.h"
 #include "ash/ime_control_delegate.h"
 #include "ash/launcher/launcher.h"
 #include "ash/launcher/launcher_model.h"
 #include "ash/screenshot_delegate.h"
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
 #include "ash/shell_window_ids.h"
 #include "ash/system/brightness/brightness_control_delegate.h"
@@ skipping 65 matching lines @@
       set_preemption_strategy(ui::LayerAnimator::REPLACE_QUEUED_ANIMATIONS);
   scoped_ptr<ui::LayerAnimationSequence> screen_rotation(
       new ui::LayerAnimationSequence(new ui::ScreenRotation(delta)));
   screen_rotation->AddObserver(ash::Shell::GetRootWindow());
   ash::Shell::GetRootWindow()->layer()->GetAnimator()->StartAnimation(
       screen_rotation.release());
   return true;
 }
 
 bool HandleToggleDesktopBackgroundMode() {
-  ash::Shell* shell = ash::Shell::GetInstance();
-  if (shell->desktop_background_mode() == ash::Shell::BACKGROUND_IMAGE)
-    shell->SetDesktopBackgroundMode(ash::Shell::BACKGROUND_SOLID_COLOR);
+  ash::DesktopBackgroundController* desktop_background_controller =
+      ash::Shell::GetInstance()->desktop_background_controller();
+  if (desktop_background_controller->desktop_background_mode() ==
+      ash::DesktopBackgroundController::BACKGROUND_IMAGE)
+    desktop_background_controller->SetDesktopBackgroundSolidColorMode();
   else
-    shell->SetDesktopBackgroundMode(ash::Shell::BACKGROUND_IMAGE);
+    desktop_background_controller->SetPreviousDesktopBackgroundImage();
   return true;
 }
 
 bool HandleToggleRootWindowFullScreen() {
   ash::Shell::GetRootWindow()->ToggleFullScreen();
   return true;
 }
 
 bool HandlePrintLayerHierarchy() {
   aura::RootWindow* root_window = ash::Shell::GetRootWindow();
@@ skipping 187 matching lines @@
       NOTREACHED() << "Unhandled action " << it->second;
   }
   return false;
 }
 
 bool AcceleratorController::CanHandleAccelerators() const {
   return true;
 }
 
 }  // namespace ash