ui: Cleanup class/struct forward declarations

ui/aura/window_event_dispatcher.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 UI_AURA_WINDOW_EVENT_DISPATCHER_H_
 #define UI_AURA_WINDOW_EVENT_DISPATCHER_H_
 
 #include <memory>
 #include <vector>
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "base/scoped_observer.h"
 #include "ui/aura/aura_export.h"
 #include "ui/aura/client/capture_delegate.h"
 #include "ui/aura/env_observer.h"
 #include "ui/aura/window_observer.h"
 #include "ui/base/cursor/cursor.h"
 #include "ui/events/event_constants.h"
 #include "ui/events/event_processor.h"
 #include "ui/events/event_targeter.h"
 #include "ui/events/gestures/gesture_recognizer.h"
 #include "ui/events/gestures/gesture_types.h"
 #include "ui/gfx/geometry/point.h"
 #include "ui/gfx/native_widget_types.h"
 
-namespace gfx {
-class Size;
-class Transform;
-}
-
 namespace ui {
 class GestureEvent;
 class GestureRecognizer;
-class KeyEvent;
 class MouseEvent;
-class ScrollEvent;
 class TouchEvent;
 }
 
 namespace aura {
 class TestScreen;
 class EnvInputStateController;
-class WindowTargeter;
 class WindowTreeHost;
 
 namespace test {
 class WindowEventDispatcherTestApi;
 }
 
 // WindowEventDispatcher orchestrates event dispatch within a window tree
 // owned by WindowTreeHost. WTH also owns the WED.
 // TODO(beng): In progress, remove functionality not directly related to
 //             event dispatch.
@@ skipping 213 matching lines @@
 
   // Used to schedule DispatchHeldEvents() when |move_hold_count_| goes to 0.
   base::WeakPtrFactory<WindowEventDispatcher> held_event_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowEventDispatcher);
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_WINDOW_EVENT_DISPATCHER_H_