Clean up WindowEventDispatcher some more.

ui/aura/window_tree_host_delegate.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_AURA_WINDOW_TREE_HOST_DELEGATE_H_
-#define UI_AURA_WINDOW_TREE_HOST_DELEGATE_H_
-
-#include "ui/aura/aura_export.h"
-
-namespace gfx {
-class Point;
-class Rect;
-class Size;
-}
-
-namespace ui {
-class Event;
-class EventProcessor;
-class KeyEvent;
-class MouseEvent;
-class ScrollEvent;
-class TouchEvent;
-}
-
-namespace aura {
-
-class RootWindow;
-
-// A private interface used by WindowTreeHost implementations to communicate
-// with their owning RootWindow.
-class AURA_EXPORT WindowTreeHostDelegate {
- public:
-  virtual void OnHostCancelMode() = 0;
-
-  // Called when the windowing system activates the window.
-  virtual void OnHostActivated() = 0;
-
-  // Called when system focus is changed to another window.
-  virtual void OnHostLostWindowCapture() = 0;
-
-  // Called when the windowing system has mouse grab because it's performing a
-  // window move on our behalf, but we should still paint as if we're active.
-  virtual void OnHostLostMouseGrab() = 0;
-
-  virtual void OnHostResized(const gfx::Size& size) = 0;
-
-  virtual void OnCursorMovedToRootLocation(const gfx::Point& root_location) = 0;
-
-  virtual WindowEventDispatcher* AsDispatcher() = 0;
-  virtual const WindowEventDispatcher* AsDispatcher() const = 0;
-
-  virtual ui::EventProcessor* GetEventProcessor() = 0;
-
- protected:
-  virtual ~WindowTreeHostDelegate() {}
-};
-
-}  // namespace aura
-
-#endif  // UI_AURA_WINDOW_TREE_HOST_DELEGATE_H_