Don't move uneditable paragraph contents in CompositeEditCommand::moveParagraphContentsToNewBlockIfN

Source/core/editing/CompositeEditCommand.cpp

 /*
  * Copyright (C) 2005, 2006, 2007, 2008 Apple 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 879 matching lines @@
     RefPtrWillBeRawPtr<Element> paragraphElement = createDefaultParagraphElement(document());
     paragraphElement->appendChild(createBreakElement(document()));
     insertNodeAt(paragraphElement, position);
     return paragraphElement.release();
 }
 
 // If the paragraph is not entirely within it's own block, create one and move the paragraph into
 // it, and return that block.  Otherwise return 0.
 PassRefPtrWillBeRawPtr<Element> CompositeEditCommand::moveParagraphContentsToNewBlockIfNecessary(const Position& pos)
 {
-    if (pos.isNull())
-        return nullptr;
-
-    document().updateLayoutIgnorePendingStylesheets();
+    ASSERT(isEditablePosition(pos, ContentIsEditable, DoNotUpdateStyle));
 
     // It's strange that this function is responsible for verifying that pos has not been invalidated
     // by an earlier call to this function.  The caller, applyBlockStyle, should do this.
     VisiblePosition visiblePos(pos, VP_DEFAULT_AFFINITY);
     VisiblePosition visibleParagraphStart(startOfParagraph(visiblePos));
     VisiblePosition visibleParagraphEnd = endOfParagraph(visiblePos);
     VisiblePosition next = visibleParagraphEnd.next();
     VisiblePosition visibleEnd = next.isNotNull() ? next : visibleParagraphEnd;
 
     Position upstreamStart = visibleParagraphStart.deepEquivalent().upstream();
@@ skipping 583 matching lines @@
 }
 
 void CompositeEditCommand::trace(Visitor* visitor)
 {
     visitor->trace(m_commands);
     visitor->trace(m_composition);
     EditCommand::trace(visitor);
 }
 
 } // namespace WebCore