Update Custom Elements API to new names.

Source/core/frame/UseCounter.h

 /*
  * Copyright (C) 2012 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:
  * 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 122 matching lines @@
         PrefixedMediaAddKey,
         PrefixedMediaGenerateKeyRequest,
         WebAudioLooping,
         DocumentClear,
         PrefixedTransitionMediaFeature,
         SVGFontElement,
         XMLDocument,
         XSLProcessingInstruction,
         XSLTProcessor,
         SVGSwitchElement,
-        PrefixedDocumentRegister,
+        UnusedSlot05, // Removed, was document.webkitRegister
         HTMLShadowElementOlderShadowRoot,
         DocumentAll,
         FormElement,
         DemotedFormElement,
         CaptureAttributeAsEnum,
         ShadowDOMPrefixedPseudo,
         ShadowDOMPrefixedCreateShadowRoot,
         ShadowDOMPrefixedShadowRoot,
         SVGAnimationElement,
         KeyboardEventKeyLocation,
@@ skipping 177 matching lines @@
 
     void updateMeasurements();
 
     OwnPtr<BitVector> m_countBits;
     BitVector m_CSSFeatureBits;
 };
 
 } // namespace WebCore
 
 #endif // UseCounter_h