aura: Track mouse button state.

ui/aura/desktop.h

 // 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.
 
 #ifndef UI_AURA_DESKTOP_H_
 #define UI_AURA_DESKTOP_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
@@ skipping 104 matching lines @@
   // Returns the desktop's dispatcher. The result should only be passed to
   // MessageLoopForUI::RunWithDispatcher() or
   // MessageLoopForUI::RunAllPendingWithDispatcher(), or used to dispatch
   // an event by |Dispatch(const NativeEvent&)| on it. It must never be stored.
   MessageLoop::Dispatcher* GetDispatcher();
 
   // Add/remove observer.
   void AddObserver(DesktopObserver* observer);
   void RemoveObserver(DesktopObserver* observer);
 
+  // Are any mouse buttons currently down?
+  bool IsMouseButtonDown() const;
+
   // Capture -------------------------------------------------------------------
 
   // Sets capture to the specified window.
   void SetCapture(Window* window);
 
   // If |window| has mouse capture, the current capture window is set to NULL.
   void ReleaseCapture(Window* window);
 
   // Overridden from Window:
   virtual void SetTransform(const ui::Transform& transform) OVERRIDE;
@@ skipping 50 matching lines @@
   static bool use_fullscreen_host_window_;
 
   // Used to schedule painting.
   base::WeakPtrFactory<Desktop> schedule_paint_factory_;
 
   Window* active_window_;
 
   // Last location seen in a mouse event.
   gfx::Point last_mouse_location_;
 
+  // ui::EventFlags containing the current state of the mouse buttons.
+  int mouse_button_flags_;
+
   // Last cursor set.  Used for testing.
   gfx::NativeCursor last_cursor_;
 
   // Are we in the process of being destroyed? Used to avoid processing during
   // destruction.
   bool in_destructor_;
 
   ObserverList<DesktopObserver> observers_;
 
   ScreenAura* screen_;
 
   // The capture window. When not-null, this window receives all the mouse and
   // touch events.
   Window* capture_window_;
 
   Window* mouse_pressed_handler_;
   Window* mouse_moved_handler_;
   Window* focused_window_;
   Window* touch_event_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(Desktop);
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_DESKTOP_H_