Add always-on-top property to app windows

ui/views/win/hwnd_message_handler.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/win/hwnd_message_handler.h"
 
 #include <dwmapi.h>
 #include <shellapi.h>
 
 #include "base/bind.h"
@@ skipping 668 matching lines @@
 }
 
 bool HWNDMessageHandler::IsMinimized() const {
   return !!::IsIconic(hwnd());
 }
 
 bool HWNDMessageHandler::IsMaximized() const {
   return !!::IsZoomed(hwnd());
 }
 
+bool HWNDMessageHandler::IsAlwaysOnTop() const {
+  return (GetWindowLong(hwnd(), GWL_EXSTYLE) & WS_EX_TOPMOST) > 0;
+}
+
 bool HWNDMessageHandler::RunMoveLoop(const gfx::Vector2d& drag_offset,
                                      bool hide_on_escape) {
   ReleaseCapture();
   MoveLoopMouseWatcher watcher(this, hide_on_escape);
 #if defined(USE_AURA)
   // In Aura, we handle touch events asynchronously. So we need to allow nested
   // tasks while in windows move loop.
   base::MessageLoop::ScopedNestableTaskAllower allow_nested(
       base::MessageLoop::current());
 #endif
@@ skipping 1538 matching lines @@
     delegate_->HandleVisibilityChanged(false);
   SetMsgHandled(FALSE);
 }
 
 void HWNDMessageHandler::HandleTouchEvents(const TouchEvents& touch_events) {
   for (size_t i = 0; i < touch_events.size(); ++i)
     delegate_->HandleTouchEvent(touch_events[i]);
 }
 
 }  // namespace views