Add clean layout DCHECK to mostForwardCaretPosition()

third_party/WebKit/Source/core/editing/commands/ReplaceSelectionCommand.cpp

 /*
  * Copyright (C) 2005, 2006, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2009, 2010, 2011 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:
  * 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
@@ skipping 1959 matching lines @@
   if (m_smartReplace || fragment.hasInterchangeNewlineAtStart() ||
       fragment.hasInterchangeNewlineAtEnd())
     return false;
 
   // e.g. when "bar" is inserted after "foo" in <div><u>foo</u></div>, "bar"
   // should not be underlined.
   if (elementToSplitToAvoidPastingIntoInlineElementsWithStyle(
           endingSelection().start()))
     return false;
 
+  // TODO(editing-dev): Use of updateStyleAndLayoutIgnorePendingStylesheets
+  // needs to be audited.  See http://crbug.com/590369 for more details.
+  document().updateStyleAndLayoutIgnorePendingStylesheets();
+
   Node* nodeAfterInsertionPos =
       mostForwardCaretPosition(endingSelection().end()).anchorNode();
   Text* textNode = toText(fragment.firstChild());
   // Our fragment creation code handles tabs, spaces, and newlines, so we don't
   // have to worry about those here.
 
   Position start = endingSelection().start();
   Position end = replaceSelectedTextInNode(textNode->data());
   if (end.isNull())
     return false;
@@ skipping 30 matching lines @@
   visitor->trace(m_startOfInsertedContent);
   visitor->trace(m_endOfInsertedContent);
   visitor->trace(m_insertionStyle);
   visitor->trace(m_documentFragment);
   visitor->trace(m_startOfInsertedRange);
   visitor->trace(m_endOfInsertedRange);
   CompositeEditCommand::trace(visitor);
 }
 
 }  // namespace blink