Cleanup mojo Wallpaper interfaces for mash.

ash/mus/context_menu_mus.cc

 // Copyright 2016 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/mus/context_menu_mus.h"
 
 #include "ash/common/shelf/wm_shelf.h"
+#include "ash/common/wallpaper/wallpaper_controller.h"
 #include "ash/common/wallpaper/wallpaper_delegate.h"
 #include "ash/common/wm_shell.h"
 #include "ash/public/cpp/shelf_types.h"
 #include "grit/ash_strings.h"
 
 namespace ash {
 
 ContextMenuMus::ContextMenuMus(WmShelf* wm_shelf)
     : ui::SimpleMenuModel(nullptr),
       wm_shelf_(wm_shelf),
@@ skipping 22 matching lines @@
   return true;
 }
 
 void ContextMenuMus::ExecuteCommand(int command_id, int event_flags) {
   if (command_id == MENU_AUTO_HIDE) {
     wm_shelf_->SetAutoHideBehavior(wm_shelf_->auto_hide_behavior() ==
                                            SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS
                                        ? SHELF_AUTO_HIDE_BEHAVIOR_NEVER
                                        : SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS);
   } else if (command_id == MENU_CHANGE_WALLPAPER) {
-    WmShell::Get()->wallpaper_delegate()->OpenSetWallpaperPage();
+    WmShell::Get()->wallpaper_controller()->OpenSetWallpaperPage();
   }
 }
 
 }  // namespace ash