Move all wallpaper file loading and decoding from DesktopBackgroundController to WallpaperManager.

ash/shell/content_client/shell_browser_main_parts.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/content_client/shell_browser_main_parts.h"
 
 #include "ash/ash_switches.h"
 #include "ash/desktop_background/desktop_background_controller.h"
 #include "ash/shell.h"
 #include "ash/shell/shell_delegate_impl.h"
@@ skipping 19 matching lines @@
 #include "ui/gfx/screen.h"
 #include "ui/message_center/message_center.h"
 #include "ui/views/test/test_views_delegate.h"
 #include "ui/wm/core/wm_state.h"
 
 #if defined(USE_X11)
 #include "ui/events/x/touch_factory_x11.h"
 #endif
 
 #if defined(OS_CHROMEOS)
+#include "chrome/browser/chromeos/login/wallpaper_manager.h"
 #include "chromeos/audio/cras_audio_handler.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #endif
 
 namespace ash {
 namespace shell {
 void InitWindowTypeLauncher();
 
 namespace {
 
@@ skipping 77 matching lines @@
   ash::Shell::GetInstance()->UpdateAfterLoginStatusChange(
       user::LOGGED_IN_USER);
 
   window_watcher_.reset(new ash::shell::WindowWatcher);
   gfx::Screen* screen = Shell::GetInstance()->GetScreen();
   screen->AddObserver(window_watcher_.get());
   delegate_->SetWatcher(window_watcher_.get());
 
   ash::shell::InitWindowTypeLauncher();
 
-  Shell::GetInstance()->desktop_background_controller()->SetDefaultWallpaper(

[Alexander Alekseev, 2014/04/09 14:37:38]

Scott, can I completely remove this call? (you've added it back in 2012).
DesktopBackgroundController will not have SetDefaultWallpaper() method, so to
set default wallpaper we would need to call UserWallpaperDelegate here.

It seems that wallpaper (now) will be set in Shell::Init() :
https://code.google.com/p/chromium/codesearch#chromium/src/ash/shell.cc&l=983

Can I completely remove SetDefaultWallpaper here?

-      false /* is_guest */);
+#if defined(OS_CHROMEOS)
+  chromeos::WallpaperManager::Get()->
+      SetDefaultWallpaperDelayed(chromeos::UserManager::kSignInUser);

[Alexander Alekseev, 2014/04/08 16:34:20]

This breaks dependencies.
Should I remove this call completely?
It would work for ChromeOS, but will it break some other platform?

[sky, 2014/04/09 16:49:36]

If unsure, try it out. We need a wallpaper to work when running ash_shell on
windows too.

+#endif
 
   ash::Shell::GetPrimaryRootWindow()->GetHost()->Show();
 }
 
 void ShellBrowserMainParts::PostMainMessageLoopRun() {
   gfx::Screen* screen = Shell::GetInstance()->GetScreen();
   screen->RemoveObserver(window_watcher_.get());
 
   window_watcher_.reset();
   delegate_->SetWatcher(NULL);
@@ skipping 16 matching lines @@
   browser_context_.reset();
 }
 
 bool ShellBrowserMainParts::MainMessageLoopRun(int* result_code) {
   base::MessageLoopForUI::current()->Run();
   return true;
 }
 
 }  // namespace shell
 }  // namespace ash