Fix sky include guards to match Chromium style

sky/engine/core/css/MediaValuesCached.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef MediaValuesCached_h
-#define MediaValuesCached_h
+#ifndef SKY_ENGINE_CORE_CSS_MEDIAVALUESCACHED_H_
+#define SKY_ENGINE_CORE_CSS_MEDIAVALUESCACHED_H_
 
 #include "sky/engine/core/css/MediaValues.h"
 
 namespace blink {
 
 class MediaValuesCached final : public MediaValues {
 public:
     struct MediaValuesCachedData {
         // Members variables must be thread safe, since they're copied to the parser thread
         int viewportWidth;
@@ skipping 60 matching lines @@
 protected:
     MediaValuesCached();
     MediaValuesCached(LocalFrame*);
     MediaValuesCached(const MediaValuesCachedData&);
 
     MediaValuesCachedData m_data;
 };
 
 } // namespace
 
-#endif // MediaValuesCached_h
+#endif  // SKY_ENGINE_CORE_CSS_MEDIAVALUESCACHED_H_