Oilpan: Replace EAGERLY_FINALIZE in EventTarget's hierarchy with pre-finalizers

third_party/WebKit/Source/modules/mediastream/RTCPeerConnection.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 395 matching lines @@
 RTCPeerConnection::RTCPeerConnection(ExecutionContext* context, RTCConfiguration* configuration, WebMediaConstraints constraints, ExceptionState& exceptionState)
     : ActiveScriptWrappable(this)
     , ActiveDOMObject(context)
     , m_signalingState(SignalingStateStable)
     , m_iceGatheringState(ICEGatheringStateNew)
     , m_iceConnectionState(ICEConnectionStateNew)
     , m_dispatchScheduledEventRunner(AsyncMethodRunner<RTCPeerConnection>::create(this, &RTCPeerConnection::dispatchScheduledEvent))
     , m_stopped(false)
     , m_closed(false)
 {
+    ThreadState::current()->registerPreFinalizer(this);
     Document* document = toDocument(getExecutionContext());
 
     // If we fail, set |m_closed| and |m_stopped| to true, to avoid hitting the assert in the destructor.
 
     if (!document->frame()) {
         m_closed = true;
         m_stopped = true;
         exceptionState.throwDOMException(NotSupportedError, "PeerConnections may not be created in detached documents.");
         return;
     }
@@ skipping 16 matching lines @@
     }
 }
 
 RTCPeerConnection::~RTCPeerConnection()
 {
     // This checks that close() or stop() is called before the destructor.
     // We are assuming that a wrapper is always created when RTCPeerConnection is created.
     DCHECK(m_closed || m_stopped);
 }
 
+void RTCPeerConnection::dispose()
+{
+    // Promptly clears a raw reference from content/ to an on-heap object
+    // so that content/ doesn't access it in a lazy sweeping phase.
+    m_peerHandler.clear();
+}
+
 ScriptPromise RTCPeerConnection::createOffer(ScriptState* scriptState, const RTCOfferOptions& options)
 {
     if (m_signalingState == SignalingStateClosed)
         return ScriptPromise::rejectWithDOMException(scriptState, DOMException::create(InvalidStateError, kSignalingStateClosedMessage));
 
     ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
     ScriptPromise promise = resolver->promise();
     RTCSessionDescriptionRequest* request = RTCSessionDescriptionRequestPromiseImpl::create(this, resolver);
     m_peerHandler->createOffer(request, convertToWebRTCOfferOptions(options));
     return promise;
@@ skipping 705 matching lines @@
 {
     visitor->trace(m_localStreams);
     visitor->trace(m_remoteStreams);
     visitor->trace(m_dispatchScheduledEventRunner);
     visitor->trace(m_scheduledEvents);
     RefCountedGarbageCollectedEventTargetWithInlineData<RTCPeerConnection>::trace(visitor);
     ActiveDOMObject::trace(visitor);
 }
 
 } // namespace blink