Oilpan: Replace most of RefPtrs for Event objects with oilpan's transition types

Source/modules/battery/BatteryManager.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 "config.h"
 #include "modules/battery/BatteryManager.h"
 
 #include "RuntimeEnabledFeatures.h"
 #include "core/events/Event.h"
 #include "modules/battery/BatteryStatus.h"
@@ skipping 42 matching lines @@
         return std::numeric_limits<double>::infinity();
 
     return m_batteryStatus->dischargingTime();
 }
 
 double BatteryManager::level()
 {
     return m_batteryStatus ? m_batteryStatus->level() : 1;
 }
 
-void BatteryManager::didChangeBatteryStatus(PassRefPtr<Event> event, PassOwnPtr<BatteryStatus> batteryStatus)
+void BatteryManager::didChangeBatteryStatus(PassRefPtrWillBeRawPtr<Event> event, PassOwnPtr<BatteryStatus> batteryStatus)
 {
     ASSERT(RuntimeEnabledFeatures::batteryStatusEnabled());
 
     m_batteryStatus = batteryStatus;
     dispatchEvent(event);
 }
 
 } // namespace WebCore