Merge 129814 - REGRESSION(r129186): Pressing enter at the end of a line deletes the line

Source/WebCore/rendering/RenderText.cpp

 /*
  * (C) 1999 Lars Knoll (knoll@kde.org)
  * (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Andrew Wellington (proton@wiretapped.net)
  * Copyright (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 1238 matching lines @@
     }
 
     // The containing block can be null in case of an orphaned tree.
     RenderBlock* containingBlock = this->containingBlock();
     if (containingBlock && !containingBlock->isRenderView())
         containingBlock->setSelectionState(state);
 }
 
 void RenderText::setTextWithOffset(PassRefPtr<StringImpl> text, unsigned offset, unsigned len, bool force)
 {
+    if (!force && equal(m_text.impl(), text.get()))
+        return;
+
     unsigned oldLen = textLength();
     unsigned newLen = text->length();
     int delta = newLen - oldLen;
     unsigned end = len ? offset + len - 1 : offset;
 
     RootInlineBox* firstRootBox = 0;
     RootInlineBox* lastRootBox = 0;
 
     bool dirtiedLines = false;
 
@@ skipping 51 matching lines @@
             curr->setLineBreakPos(curr->lineBreakPos() + delta);
     }
 
     // If the text node is empty, dirty the line where new text will be inserted.
     if (!firstTextBox() && parent()) {
         parent()->dirtyLinesFromChangedChild(this);
         dirtiedLines = true;
     }
 
     m_linesDirty = dirtiedLines;
-    setText(text, force);
+    setText(text, force || dirtiedLines);
 }
 
 void RenderText::transformText()
 {
     if (RefPtr<StringImpl> textToTransform = originalText())
         setText(textToTransform.release(), true);
 }
 
 static inline bool isInlineFlowOrEmptyText(const RenderObject* o)
 {
@@ skipping 570 matching lines @@
 
     SecureTextTimer* secureTextTimer = gSecureTextTimers->get(this);
     if (!secureTextTimer) {
         secureTextTimer = new SecureTextTimer(this);
         gSecureTextTimers->add(this, secureTextTimer);
     }
     secureTextTimer->restartWithNewText(lastTypedCharacterOffset);
 }
 
 } // namespace WebCore