Add hooks for capturing meaningful text info, gently.

Source/core/dom/Document.h

 /*
  * 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, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
@@ skipping 549 matching lines @@
     bool isLoadCompleted();
 
     enum ParsingState {
         Parsing,
         InDOMContentLoaded,
         FinishedParsing
     };
     void setParsingState(ParsingState);
     bool parsing() const { return m_parsingState == Parsing; }
     bool isInDOMContentLoaded() const { return m_parsingState == InDOMContentLoaded; }
+    bool hasFinishedParsing() const { return m_parsingState == FinishedParsing; }
 
     bool shouldScheduleLayout() const;
     int elapsedTime() const;
 
     TextLinkColors& textLinkColors() { return m_textLinkColors; }
     VisitedLinkState& visitedLinkState() const { return *m_visitedLinkState; }
 
     MouseEventWithHitTestResults prepareMouseEvent(const HitTestRequest&, const LayoutPoint&, const PlatformMouseEvent&);
 
     /* Newly proposed CSS3 mechanism for selecting alternate
@@ skipping 843 matching lines @@
 DEFINE_TYPE_CASTS(TreeScope, Document, document, true, true);
 
 } // namespace blink
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 CORE_EXPORT void showLiveDocumentInstances();
 #endif
 
 #endif // Document_h