Use C++11 range-based loop for core/css

Source/core/css/CSSCrossfadeValue.cpp

 /*
  * Copyright (C) 2011 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 171 matching lines @@
     if (!fromImage || !toImage)
         return Image::nullImage();
 
     m_generatedImage = CrossfadeGeneratedImage::create(fromImage, toImage, m_percentageValue->getFloatValue(), fixedSize(renderer), size);
 
     return m_generatedImage.release();
 }
 
 void CSSCrossfadeValue::crossfadeChanged(const IntRect&)
 {
-    RenderObjectSizeCountMap::const_iterator end = clients().end();
-    for (RenderObjectSizeCountMap::const_iterator curr = clients().begin(); curr != end; ++curr) {
-        RenderObject* client = const_cast<RenderObject*>(curr->key);
+    for (const auto& curr : clients()) {
+        RenderObject* client = const_cast<RenderObject*>(curr.key);
         client->imageChanged(static_cast<WrappedImagePtr>(this));
     }
 }
 
 void CSSCrossfadeValue::CrossfadeSubimageObserverProxy::imageChanged(ImageResource*, const IntRect* rect)
 {
     if (m_ready)
         m_ownerValue->crossfadeChanged(*rect);
 }
 
@@ skipping 15 matching lines @@
 
 void CSSCrossfadeValue::traceAfterDispatch(Visitor* visitor)
 {
     visitor->trace(m_fromValue);
     visitor->trace(m_toValue);
     visitor->trace(m_percentageValue);
     CSSImageGeneratorValue::traceAfterDispatch(visitor);
 }
 
 } // namespace blink