Converts overview to use common ash types

ash/shell.h

 // 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.
 
 #ifndef ASH_SHELL_H_
 #define ASH_SHELL_H_
 
 #include <memory>
 #include <utility>
 #include <vector>
@@ skipping 109 matching lines @@
 class NewWindowDelegate;
 class OverlayEventFilter;
 class PartialMagnificationController;
 class PointerWatcherDelegate;
 class PowerButtonController;
 class PowerEventObserver;
 class ProjectingObserver;
 class ResizeShadowController;
 class ResolutionNotificationController;
 class RootWindowController;
+class ScopedOverviewAnimationSettingsFactoryAura;
 class ScopedTargetRootWindow;
 class ScreenAsh;
 class ScreenOrientationController;
 class ScreenshotController;
 class ScreenPositionController;
 class SessionStateDelegate;
 class Shelf;
 class ShelfDelegate;
 class ShelfItemDelegateManager;
 class ShelfModel;
@@ skipping 520 matching lines @@
       aura::client::ActivationChangeObserver::ActivationReason reason,
       aura::Window* gained_active,
       aura::Window* lost_active) override;
 
   static Shell* instance_;
 
   // If set before the Shell is initialized, the mouse cursor will be hidden
   // when the screen is initially created.
   static bool initially_hide_cursor_;
 
+  std::unique_ptr<ScopedOverviewAnimationSettingsFactoryAura>
+      scoped_overview_animation_settings_factory_;
   std::unique_ptr<wm::WmGlobalsAura> wm_globals_;
 
   // When no explicit target display/RootWindow is given, new windows are
   // created on |scoped_target_root_window_| , unless NULL in
   // which case they are created on |target_root_window_|.
   // |target_root_window_| never becomes NULL during the session.
   aura::Window* target_root_window_;
   aura::Window* scoped_target_root_window_;
 
   // The CompoundEventFilter owned by aura::Env object.
@@ skipping 134 matching lines @@
   bool in_mus_ = false;
 
   std::unique_ptr<KeyboardUI> keyboard_ui_;
 
   DISALLOW_COPY_AND_ASSIGN(Shell);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SHELL_H_