Oilpan: move HistoryItem to the heap.

Source/core/loader/FrameLoader.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008 Alp Toker <alp@atoker.com>
  * Copyright (C) Research In Motion Limited 2009. All rights reserved.
  * Copyright (C) 2011 Kris Jordan <krisjordan@gmail.com>
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ skipping 119 matching lines @@
     // Verify that this FrameLoader has been detached.
     ASSERT(!m_progressTracker);
 }
 
 void FrameLoader::trace(Visitor* visitor)
 {
     visitor->trace(m_frame);
     visitor->trace(m_mixedContentChecker);
     visitor->trace(m_progressTracker);
     visitor->trace(m_fetchContext);
+    visitor->trace(m_currentItem);
+    visitor->trace(m_provisionalItem);
+    visitor->trace(m_deferredHistoryLoad);
 }
 
 void FrameLoader::init()
 {
     ResourceRequest initialRequest(KURL(ParsedURLString, emptyString()));
     initialRequest.setRequestContext(WebURLRequest::RequestContextInternal);
     initialRequest.setFrameType(m_frame->isMainFrame() ? WebURLRequest::FrameTypeTopLevel : WebURLRequest::FrameTypeNested);
     m_provisionalDocumentLoader = client()->createDocumentLoader(m_frame, initialRequest, SubstituteData());
     m_provisionalDocumentLoader->startLoadingMainResource();
     m_frame->document()->cancelParsing();
@@ skipping 1292 matching lines @@
     // FIXME: We need a way to propagate sandbox flags to out-of-process frames.
     Frame* parentFrame = m_frame->tree().parent();
     if (parentFrame && parentFrame->isLocalFrame())
         flags |= toLocalFrame(parentFrame)->document()->sandboxFlags();
     if (FrameOwner* frameOwner = m_frame->owner())
         flags |= frameOwner->sandboxFlags();
     return flags;
 }
 
 } // namespace blink