chromeos: Rename ash::WmShelf to Shelf

ash/system/virtual_keyboard/virtual_keyboard_tray.h

 // Copyright 2014 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.
 
 #ifndef ASH_SYSTEM_VIRTUAL_KEYBOARD_VIRTUAL_KEYBOARD_TRAY_H_
 #define ASH_SYSTEM_VIRTUAL_KEYBOARD_VIRTUAL_KEYBOARD_TRAY_H_
 
 #include "ash/keyboard/keyboard_ui_observer.h"
 #include "ash/system/tray/tray_background_view.h"
 #include "base/macros.h"
 #include "ui/keyboard/keyboard_controller_observer.h"
 
 namespace views {
 class ImageView;
 }
 
 namespace ash {
 
 // TODO(sky): make this visible on non-chromeos platforms.
 class VirtualKeyboardTray : public TrayBackgroundView,
                             public KeyboardUIObserver,
                             public keyboard::KeyboardControllerObserver {
  public:
-  explicit VirtualKeyboardTray(WmShelf* wm_shelf);
+  explicit VirtualKeyboardTray(Shelf* shelf);
   ~VirtualKeyboardTray() override;
 
   // TrayBackgroundView:
   base::string16 GetAccessibleNameForTray() override;
   void HideBubbleWithView(const views::TrayBubbleView* bubble_view) override;
   void ClickedOutsideBubble() override;
   bool PerformAction(const ui::Event& event) override;
 
   // KeyboardUIObserver:
   void OnKeyboardEnabledStateChanged(bool new_enabled) override;
 
   // keyboard::KeyboardControllerObserver:
   void OnKeyboardBoundsChanging(const gfx::Rect& new_bounds) override;
   void OnKeyboardClosed() override;
 
  private:
   void ObserveKeyboardController();
   void UnobserveKeyboardController();
 
   // Weak pointer, will be parented by TrayContainer for its lifetime.
   views::ImageView* icon_;
 
-  WmShelf* wm_shelf_;
+  Shelf* shelf_;
 
   DISALLOW_COPY_AND_ASSIGN(VirtualKeyboardTray);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SYSTEM_VIRTUAL_KEYBOARD_VIRTUAL_KEYBOARD_TRAY_H_