Add support for MouseEnter/MouseExit event types to be sent to aura::Windows.

ui/aura/event.cc

 // Copyright (c) 2011 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.
 
 #include "ui/aura/event.h"
 
 #include "ui/aura/window.h"
 
 namespace aura {
 
@@ skipping 31 matching lines @@
                            const gfx::Point& location,
                            int flags)
     : Event(type, flags),
       location_(location) {
 }
 
 MouseEvent::MouseEvent(const MouseEvent& model, Window* source, Window* target)
     : LocatedEvent(model, source, target) {
 }
 
+MouseEvent::MouseEvent(const MouseEvent& model,
+                       Window* source,
+                       Window* target,
+                       ui::EventType type)
+    : LocatedEvent(model, source, target) {
+  set_type(type);
+}
+
 MouseEvent::MouseEvent(ui::EventType type,
                        const gfx::Point& location,
                        int flags)
     : LocatedEvent(type, location, flags) {
 }
 
 KeyEvent::KeyEvent(ui::EventType type,
                    ui::KeyboardCode key_code,
                    int flags)
     : Event(type, flags),
       key_code_(key_code) {
 }
 
 }  // namespace aura