Add always-on-top property to app windows

ui/views/widget/desktop_aura/desktop_native_widget_aura.cc

 // 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.
 
 #include "ui/views/widget/desktop_aura/desktop_native_widget_aura.h"
 
 #include "base/bind.h"
 #include "ui/aura/client/activation_client.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/client/cursor_client.h"
@@ skipping 627 matching lines @@
 
 bool DesktopNativeWidgetAura::IsActive() const {
   return window_ && desktop_root_window_host_->IsActive();
 }
 
 void DesktopNativeWidgetAura::SetAlwaysOnTop(bool always_on_top) {
   if (window_)
     desktop_root_window_host_->SetAlwaysOnTop(always_on_top);
 }
 
+bool DesktopNativeWidgetAura::IsAlwaysOnTop() const {
+  return window_ && desktop_root_window_host_->IsAlwaysOnTop();
+}
+
 void DesktopNativeWidgetAura::Maximize() {
   if (window_)
     desktop_root_window_host_->Maximize();
 }
 
 void DesktopNativeWidgetAura::Minimize() {
   if (window_)
     desktop_root_window_host_->Minimize();
 }
 
@@ skipping 369 matching lines @@
 
 ui::EventHandler* DesktopNativeWidgetAura::GetEventHandler() {
   return this;
 }
 
 void DesktopNativeWidgetAura::UpdateWindowTransparency() {
   window_->SetTransparent(ShouldUseNativeFrame());
 }
 
 }  // namespace views