Add option to dump line box tree when dumping layout tree.

Source/web/WebLocalFrameImpl.cpp

 /*
  * Copyright (C) 2009 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 1549 matching lines @@
 {
     if (!frame())
         return WebString();
     return createMarkup(frame()->document());
 }
 
 WebString WebLocalFrameImpl::layoutTreeAsText(LayoutAsTextControls toShow) const
 {
     LayoutAsTextBehavior behavior = LayoutAsTextShowAllLayers;
 
+    if (toShow & LayoutAsTextWithLineTrees)
+        behavior |= LayoutAsTextShowLineTrees;
+
     if (toShow & LayoutAsTextDebug)
         behavior |= LayoutAsTextShowCompositedLayers | LayoutAsTextShowAddresses | LayoutAsTextShowIDAndClass | LayoutAsTextShowLayerNesting;
 
     if (toShow & LayoutAsTextPrinting)
         behavior |= LayoutAsTextPrintingMode;
 
     return externalRepresentation(frame(), behavior);
 }
 
 WebString WebLocalFrameImpl::markerTextForListItem(const WebElement& webElement) const
@@ skipping 532 matching lines @@
 {
     m_frameWidget = frameWidget;
 }
 
 WebFrameWidgetImpl* WebLocalFrameImpl::frameWidget() const
 {
     return m_frameWidget;
 }
 
 } // namespace blink