Add a test that we resume commits after inserting the body.

Source/core/dom/Document.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008, 2009, 2011, 2012 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) Research In Motion Limited 2010-2011. All rights reserved.
@@ skipping 2363 matching lines @@
 
 PassRefPtrWillBeRawPtr<DocumentParser> Document::implicitOpen(ParserSynchronizationPolicy parserSyncPolicy)
 {
     cancelParsing();
 
     removeChildren();
     ASSERT(!m_focusedElement);
 
     setCompatibilityMode(NoQuirksMode);
 
+    if (frameHost() && frameHost()->chromeClient().disableThreadedParsingForUnitTests())
+        parserSyncPolicy = ForceSynchronousParsing;
+
     m_parserSyncPolicy = parserSyncPolicy;
     m_parser = createParser();
     setParsingState(Parsing);
     setReadyState(Loading);
 
     return m_parser;
 }
 
 HTMLElement* Document::body() const
 {
@@ skipping 3310 matching lines @@
 #ifndef NDEBUG
 using namespace blink;
 void showLiveDocumentInstances()
 {
     Document::WeakDocumentSet& set = Document::liveDocumentSet();
     fprintf(stderr, "There are %u documents currently alive:\n", set.size());
     for (Document* document : set)
         fprintf(stderr, "- Document %p URL: %s\n", document, document->url().string().utf8().data());
 }
 #endif