Fix sky include guards to match Chromium style

sky/engine/core/rendering/compositing/CompositingState.h

 // Copyright 2013 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 CompositingState_h
-#define CompositingState_h
+#ifndef SKY_ENGINE_CORE_RENDERING_COMPOSITING_COMPOSITINGSTATE_H_
+#define SKY_ENGINE_CORE_RENDERING_COMPOSITING_COMPOSITINGSTATE_H_
 
 namespace blink {
 
 enum CompositingState {
     // The layer paints into its enclosing composited ancestor.
     NotComposited = 0,
 
     // The layer is composited, but its contents still paint into enclosing composited ancestor.
     // In this state, paint invalidations must be sent to the enclosing composited ancestor.
     // Typically this happens when a layer's properties need to be represented in the compositor
     // output data structures, but it doesn't actually have any other reasons to be composited.
     HasOwnBackingButPaintsIntoAncestor = 1,
 
     PaintsIntoOwnBacking = 2,
 
     // In this state, the RenderLayer subtree paints into a backing that is shared by
     // several RenderLayer subtrees.
     PaintsIntoGroupedBacking = 3
 };
 
 } // namespace blink
 
-#endif // CompositingState_h
+#endif  // SKY_ENGINE_CORE_RENDERING_COMPOSITING_COMPOSITINGSTATE_H_