Oilpan: add missing tracing of InspectorTracingAgent objects.

Source/core/inspector/InspectorTracingAgent.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 "core/inspector/InspectorTracingAgent.h"
 
 #include "core/inspector/IdentifiersFactory.h"
 #include "core/inspector/InspectorClient.h"
 #include "core/inspector/InspectorState.h"
 #include "core/inspector/InspectorTraceEvents.h"
 #include "core/inspector/InspectorWorkerAgent.h"
+#include "core/page/Page.h"
 #include "platform/TraceEvent.h"
 
 namespace blink {
 
 namespace TracingAgentState {
 const char sessionId[] = "sessionId";
 }
 
 namespace {
 const char devtoolsMetadataEventCategory[] = TRACE_DISABLED_BY_DEFAULT("devtools.timeline");
 }
 
 InspectorTracingAgent::InspectorTracingAgent(InspectorClient* client, InspectorWorkerAgent* workerAgent, Page* page)
     : InspectorBaseAgent<InspectorTracingAgent>("Tracing")
     , m_layerTreeId(0)
     , m_client(client)
     , m_frontend(0)
     , m_workerAgent(workerAgent)
     , m_page(page)
 {
 }
 
+void InspectorTracingAgent::trace(Visitor* visitor)
+{
+    visitor->trace(m_workerAgent);
+    visitor->trace(m_page);
+    InspectorBaseAgent<InspectorTracingAgent>::trace(visitor);
+}
+
 void InspectorTracingAgent::restore()
 {
     emitMetadataEvents();
 }
 
 void InspectorTracingAgent::start(ErrorString*, const String* categoryFilter, const String*, const double*, PassRefPtrWillBeRawPtr<StartCallback> callback)
 {
     ASSERT(m_state->getString(TracingAgentState::sessionId).isEmpty());
     m_state->setString(TracingAgentState::sessionId, IdentifiersFactory::createIdentifier());
     m_client->enableTracing(categoryFilter ? *categoryFilter : String());
@@ skipping 37 matching lines @@
     resetSessionId();
 }
 
 void InspectorTracingAgent::resetSessionId()
 {
     m_state->remove(TracingAgentState::sessionId);
     m_workerAgent->setTracingSessionId(sessionId());
 }
 
 }