Fix line height when changing multiplier.

Source/core/rendering/FastTextAutosizer.cpp

 /*
  * Copyright (C) 2013 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 784 matching lines @@
     ASSERT(renderer);
     RenderStyle* currentStyle = renderer->style();
     if (currentStyle->textAutosizingMultiplier() == multiplier)
         return;
 
     // We need to clone the render style to avoid breaking style sharing.
     RefPtr<RenderStyle> style = RenderStyle::clone(currentStyle);
     style->setTextAutosizingMultiplier(multiplier);
     style->setUnique();
     renderer->setStyleInternal(style.release());
+
+    if (renderer->isRenderBlock())
+        toRenderBlock(renderer)->invalidateLineHeight();
 }
 
 bool FastTextAutosizer::isWiderOrNarrowerDescendant(Cluster* cluster)
 {
     if (!cluster->m_parent || !mightBeWiderOrNarrowerDescendant(cluster->m_root))
         return true;
 
     const RenderBlock* parentDeepestBlockContainingAllText = deepestBlockContainingAllText(cluster->m_parent);
     ASSERT(m_blocksThatHaveBegunLayout.contains(cluster->m_root));
     ASSERT(m_blocksThatHaveBegunLayout.contains(parentDeepestBlockContainingAllText));
@@ skipping 111 matching lines @@
         m_textAutosizer = 0;
 }
 
 FastTextAutosizer::LayoutScope::~LayoutScope()
 {
     if (m_textAutosizer)
         m_textAutosizer->endLayout(m_block);
 }
 
 } // namespace WebCore