Asynchronously load wallpapers when user pod is selected.

ash/shell.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/shell.h"
 
 #include <algorithm>
 
 #include "ash/app_list/app_list.h"
 #include "ash/ash_switches.h"
@@ skipping 868 matching lines @@
   workspace_controller_->workspace_manager()->set_shelf(shelf_layout_manager);
   shelf_layout_manager->set_workspace_manager(
       workspace_controller_->workspace_manager());
 
   aura::Window* always_on_top_container =
       GetContainer(internal::kShellWindowId_AlwaysOnTopContainer);
   always_on_top_container->SetLayoutManager(
       new internal::BaseLayoutManager(
           always_on_top_container->GetRootWindow()));
 
-  // Create desktop background widget.
-  desktop_background_controller_->SetDesktopBackgroundImageMode();
+  // Before login, the desktop background set to the default wallpaper.
+  // When browser crashes, this will load user's wallpaper from resources (slow
+  // on Alex).
+  desktop_background_controller_->SetLoggedInUserWallpaper();
 
   // Create Panel layout manager
   if (CommandLine::ForCurrentProcess()->
       HasSwitch(switches::kAuraPanelManager)) {
     aura::Window* panel_container = GetContainer(
         internal::kShellWindowId_PanelContainer);
     panel_layout_manager_ =
         new internal::PanelLayoutManager(panel_container);
     panel_container->SetEventFilter(
         new internal::PanelWindowEventFilter(
             panel_container, panel_layout_manager_));
     panel_container->SetLayoutManager(panel_layout_manager_);
   }
 }
 
 void Shell::DisableWorkspaceGridLayout() {
   if (workspace_controller_.get())
     workspace_controller_->workspace_manager()->set_grid_size(0);
 }
 
 }  // namespace ash