Use template specialization to generate WindowProperty code

ui/wm/core/transient_window_manager.cc

 // Copyright 2014 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/wm/core/transient_window_manager.h"
 
 #include <algorithm>
 #include <functional>
 
 #include "base/auto_reset.h"
 #include "base/stl_util.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_property.h"
 #include "ui/wm/core/transient_window_observer.h"
 #include "ui/wm/core/transient_window_stacking_client.h"
 #include "ui/wm/core/window_util.h"
 
 using aura::Window;
 
+DECLARE_WINDOW_PROPERTY_TYPE(wm::TransientWindowManager*);
+
 namespace wm {
 namespace {
 
 DEFINE_OWNED_WINDOW_PROPERTY_KEY(TransientWindowManager, kPropertyKey, NULL);
 
 }  // namespace
 
 TransientWindowManager::~TransientWindowManager() {
 }
 
@@ skipping 181 matching lines @@
 
   // Destroy transient children, only after we've removed ourselves from our
   // parent, as destroying an active transient child may otherwise attempt to
   // refocus us.
   Windows transient_children(transient_children_);
   STLDeleteElements(&transient_children);
   DCHECK(transient_children_.empty());
 }
 
 }  // namespace wm