Add always-on-top property to app windows

ui/views/widget/widget.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_VIEWS_WIDGET_WIDGET_H_
 #define UI_VIEWS_WIDGET_WIDGET_H_
 
 #include <set>
 #include <stack>
 #include <vector>
@@ skipping 443 matching lines @@
 
   // Prevents the window from being rendered as deactivated. This state is
   // reset automatically as soon as the window becomes activated again. There is
   // no ability to control the state through this API as this leads to sync
   // problems.
   void DisableInactiveRendering();
 
   // Sets the widget to be on top of all other widgets in the windowing system.
   void SetAlwaysOnTop(bool on_top);
 
+  // Returns whether the widget has been set to be on top of most other widgets
+  // in the windowing system.
+  bool IsAlwaysOnTop() const;
+
   // Maximizes/minimizes/restores the window.
   void Maximize();
   void Minimize();
   void Restore();
 
   // Whether or not the window is maximized or minimized.
   virtual bool IsMaximized() const;
   bool IsMinimized() const;
 
   // Accessors for fullscreen state.
@@ skipping 414 matching lines @@
   // True when window movement via mouse interaction with the frame should be
   // disabled.
   bool movement_disabled_;
 
   DISALLOW_COPY_AND_ASSIGN(Widget);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_WIDGET_H_