Fixes bugs in cursor handling

services/ui/ws/event_dispatcher.h

 // Copyright 2015 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 SERVICES_UI_WS_EVENT_DISPATCHER_H_
 #define SERVICES_UI_WS_EVENT_DISPATCHER_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 96 matching lines @@
   // and if that's the case, releases the capture.
   void ReleaseCaptureBlockedByAnyModalWindow();
 
   // Retrieves the ServerWindow of the last mouse move. If there is no valid
   // window event target this falls back to the root of the display. In general
   // this is not null, but may be null during shutdown.
   ServerWindow* mouse_cursor_source_window() const {
     return mouse_cursor_source_window_;
   }
 
+  // Returns the window the mouse cursor is taken from. This does not take
+  // into account drags. In other words if there is a drag on going the mouse
+  // comes comes from a different window.
+  const ServerWindow* GetWindowForMouseCursor() const;
+
   // If the mouse cursor is still over |mouse_cursor_source_window_|, updates
   // whether we are in the non-client area. Used when
   // |mouse_cursor_source_window_| has changed its properties.
   void UpdateNonClientAreaForCurrentWindow();
 
   // Possibly updates the cursor. If we aren't in an implicit capture, we take
   // the last known location of the mouse pointer, and look for the
   // ServerWindow* under it.
   void UpdateCursorProviderByLastKnownLocation();
 
@@ skipping 152 matching lines @@
       AcceleratorMatchPhase::ANY;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(EventDispatcher);
 };
 
 }  // namespace ws
 }  // namespace ui
 
 #endif  // SERVICES_UI_WS_EVENT_DISPATCHER_H_