ui: Cleanup class/struct forward declarations

ui/wm/core/window_animations.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 UI_WM_CORE_WINDOW_ANIMATIONS_H_
 #define UI_WM_CORE_WINDOW_ANIMATIONS_H_
 
 #include <vector>
 
 #include "base/macros.h"
 #include "ui/compositor/scoped_layer_animation_settings.h"
 #include "ui/wm/wm_export.h"
 
 namespace aura {
 class Window;
 }
 namespace base {
 class TimeDelta;
 }
-namespace gfx {
-class Rect;
-}
-namespace ui {
-class ImplicitAnimationObserver;
-class Layer;
-class LayerAnimationSequence;
-}
 
 namespace wm {
 
 // A variety of canned animations for window transitions.
 enum WindowVisibilityAnimationType {
   WINDOW_VISIBILITY_ANIMATION_TYPE_DEFAULT = 0,     // Default. Lets the system
                                                     // decide based on window
                                                     // type.
   WINDOW_VISIBILITY_ANIMATION_TYPE_DROP,            // Window shrinks in.
   WINDOW_VISIBILITY_ANIMATION_TYPE_VERTICAL,        // Vertical Glenimation.
@@ skipping 71 matching lines @@
 WM_EXPORT bool AnimateWindow(aura::Window* window, WindowAnimationType type);
 
 // Returns true if window animations are disabled for |window|. Window
 // animations are enabled by default. If |window| is NULL, this just checks
 // if the global flag disabling window animations is present.
 WM_EXPORT bool WindowAnimationsDisabled(aura::Window* window);
 
 }  // namespace wm
 
 #endif  // UI_WM_CORE_WINDOW_ANIMATIONS_H_