Introduce RootWindowHostDelegate. The RootWindowHost performs most of its communication with RootWi…

ui/aura/root_window_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_ROOT_WINDOW_HOST_DELEGATE_H_
+#define UI_AURA_ROOT_WINDOW_HOST_DELEGATE_H_
+
+namespace gfx {
+class Size;
+}
+
+namespace aura {
+
+class KeyEvent;
+class MouseEvent;
+class RootWindow;
+class ScrollEvent;
+class TouchEvent;
+
+// A private interface used by RootWindowHost implementations to communicate
+// with their owning RootWindow.
+class AURA_EXPORT RootWindowHostDelegate {
+ public:
+  virtual bool OnHostKeyEvent(KeyEvent* event) = 0;
+  virtual bool OnHostMouseEvent(MouseEvent* event) = 0;
+  virtual bool OnHostScrollEvent(ScrollEvent* event) = 0;
+  virtual bool OnHostTouchEvent(TouchEvent* event) = 0;
+
+  virtual void OnHostLostCapture() = 0;
+
+  virtual void OnHostPaint() = 0;
+
+  virtual void OnHostResized(const gfx::Size& size) = 0;
+
+  virtual float GetDeviceScaleFactor() = 0;
+
+  virtual RootWindow* AsRootWindow() = 0;
+
+ protected:
+  virtual ~RootWindowHostDelegate() {}
+};
+
+}  // namespace aura
+
+#endif  // UI_AURA_ROOT_WINDOW_HOST_DELEGATE_H_