Add always-on-top property to app windows

ui/views/widget/native_widget_private.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_NATIVE_WIDGET_PRIVATE_H_
 #define UI_VIEWS_WIDGET_NATIVE_WIDGET_PRIVATE_H_
 
 #include "base/strings/string16.h"
 #include "ui/base/ui_base_types.h"
 #include "ui/gfx/native_widget_types.h"
@@ skipping 170 matching lines @@
   virtual void Hide() = 0;
   // Invoked if the initial show should maximize the window. |restored_bounds|
   // is the bounds of the window when not maximized.
   virtual void ShowMaximizedWithBounds(const gfx::Rect& restored_bounds) = 0;
   virtual void ShowWithWindowState(ui::WindowShowState show_state) = 0;
   virtual bool IsVisible() const = 0;
   virtual void Activate() = 0;
   virtual void Deactivate() = 0;
   virtual bool IsActive() const = 0;
   virtual void SetAlwaysOnTop(bool always_on_top) = 0;
+  virtual bool IsAlwaysOnTop() const = 0;
   virtual void Maximize() = 0;
   virtual void Minimize() = 0;
   virtual bool IsMaximized() const = 0;
   virtual bool IsMinimized() const = 0;
   virtual void Restore() = 0;
   virtual void SetFullscreen(bool fullscreen) = 0;
   virtual bool IsFullscreen() const = 0;
   virtual void SetOpacity(unsigned char opacity) = 0;
   virtual void SetUseDragFrame(bool use_drag_frame) = 0;
   virtual void FlashFrame(bool flash) = 0;
@@ skipping 19 matching lines @@
 
   // Overridden from NativeWidget:
   virtual internal::NativeWidgetPrivate* AsNativeWidgetPrivate() OVERRIDE;
   virtual ui::EventHandler* GetEventHandler() = 0;
 };
 
 }  // namespace internal
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_NATIVE_WIDGET_PRIVATE_H_