Improve DEFINE_STATIC_LOCAL()'s handling of Blink GCed objects.

third_party/WebKit/Source/modules/device_light/DeviceLightDispatcher.cpp

 // 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 "modules/device_light/DeviceLightDispatcher.h"
 
 #include "modules/device_light/DeviceLightController.h"
 #include "public/platform/Platform.h"
 
 namespace blink {
 
 DeviceLightDispatcher& DeviceLightDispatcher::instance()
 {
-    DEFINE_STATIC_LOCAL(Persistent<DeviceLightDispatcher>, deviceLightDispatcher, (new DeviceLightDispatcher()));
-    return *deviceLightDispatcher;
+    DEFINE_STATIC_LOCAL(DeviceLightDispatcher, deviceLightDispatcher, (new DeviceLightDispatcher));
+    return deviceLightDispatcher;
 }
 
 DeviceLightDispatcher::DeviceLightDispatcher()
     : m_lastDeviceLightData(-1)
 {
 }
 
 DeviceLightDispatcher::~DeviceLightDispatcher()
 {
 }
@@ skipping 19 matching lines @@
     m_lastDeviceLightData = value;
     notifyControllers();
 }
 
 double DeviceLightDispatcher::latestDeviceLightData() const
 {
     return m_lastDeviceLightData;
 }
 
 } // namespace blink