Make Range.detach() a no-op

Source/core/editing/FormatBlockCommand.cpp

 /*
  * Copyright (C) 2006 Apple Computer, 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 88 matching lines @@
 
     if (wasEndOfParagraph && !isEndOfParagraph(VisiblePosition(lastParagraphInBlockNode)) && !isStartOfParagraph(VisiblePosition(lastParagraphInBlockNode)))
         insertBlockPlaceholder(lastParagraphInBlockNode);
 }
 
 Element* FormatBlockCommand::elementForFormatBlockCommand(Range* range)
 {
     if (!range)
         return 0;
 
-    Node* commonAncestor = range->commonAncestorContainer(IGNORE_EXCEPTION);
+    Node* commonAncestor = range->commonAncestorContainer();
     while (commonAncestor && !isElementForFormatBlock(commonAncestor))
         commonAncestor = commonAncestor->parentNode();
 
     if (!commonAncestor)
         return 0;
 
     Element* rootEditableElement = range->startContainer()->rootEditableElement();
     if (!rootEditableElement || commonAncestor->contains(rootEditableElement))
         return 0;
 
@@ skipping 40 matching lines @@
             return n;
         if (isBlock(n))
             lastBlock = n;
         if (isListElement(n))
             return n->parentNode()->rendererIsEditable() ? n->parentNode() : n;
     }
     return lastBlock;
 }
 
 }