Oilpan: move BatteryStatus to the heap.

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 "modules/battery/BatteryDispatcher.h"
 #include "modules/battery/BatteryStatus.h"
 #include "platform/RuntimeEnabledFeatures.h"
 
 namespace WebCore {
 
 PassRefPtrWillBeRawPtr<BatteryManager> BatteryManager::create(ExecutionContext* context)
 {
     RefPtrWillBeRawPtr<BatteryManager> batteryManager(adoptRefWillBeRefCountedGarbageCollected(new BatteryManager(context)));
     batteryManager->suspendIfNeeded();
     return batteryManager.release();
 }
 
 BatteryManager::~BatteryManager()
 {
     stopUpdating();

[haraken, 2014/06/19 10:59:16]

This calls unregisterWithDispatcher(), which removes |this| object from
DeviceEventDispatcherBase::m_controllers.

In a follow-up, you might want to move the DeviceEventDispatcherBase's hierarchy
to the heap and replace the logic with weak processing (you can make
m_controllers a hash set of the weak members).

 }
 
 BatteryManager::BatteryManager(ExecutionContext* context)
     : ActiveDOMObject(context)
     , DeviceEventControllerBase(toDocument(context)->page())
     , m_batteryStatus(BatteryStatus::create())
     , m_state(NotStarted)
 {
 }
 
@@ skipping 35 matching lines @@
 double BatteryManager::level()
 {
     return m_batteryStatus->level();
 }
 
 void BatteryManager::didUpdateData()
 {
     ASSERT(RuntimeEnabledFeatures::batteryStatusEnabled());
     ASSERT(m_state != NotStarted);
 
-    RefPtr<BatteryStatus> oldStatus = m_batteryStatus;
+    RefPtrWillBeRawPtr<BatteryStatus> oldStatus = m_batteryStatus;
     m_batteryStatus = BatteryDispatcher::instance().latestData();
 
+#if !ENABLE(OILPAN)
     // BatteryDispatcher also holds a reference to m_batteryStatus.
     ASSERT(m_batteryStatus->refCount() > 1);
+#endif
 
     if (m_state == Pending) {
         ASSERT(m_resolver);
         m_state = Resolved;
         m_resolver->resolve(this);
         return;
     }
 
     Document* document = toDocument(executionContext());
     if (document->activeDOMObjectsAreSuspended() || document->activeDOMObjectsAreStopped())
@@ skipping 37 matching lines @@
     m_hasEventListener = true;
     startUpdating();
 }
 
 void BatteryManager::stop()
 {
     m_hasEventListener = false;
     stopUpdating();
 }
 
+void BatteryManager::trace(Visitor* visitor)
+{
+    visitor->trace(m_batteryStatus);
+    EventTargetWithInlineData::trace(visitor);
+}
+
 } // namespace WebCore