Remove forward declarations from Source/core/dom/custom

Source/core/dom/custom/CustomElementUpgradeCandidateMap.h

 /*
  * 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 22 matching lines @@
 
 #include "core/dom/custom/CustomElementDescriptor.h"
 #include "core/dom/custom/CustomElementDescriptorHash.h"
 #include "core/dom/custom/CustomElementObserver.h"
 #include "wtf/HashMap.h"
 #include "wtf/LinkedHashSet.h"
 #include "wtf/Noncopyable.h"
 
 namespace blink {
 
-class Element;
-
 class CustomElementUpgradeCandidateMap FINAL : public CustomElementObserver {
     WTF_MAKE_NONCOPYABLE(CustomElementUpgradeCandidateMap);
 public:
     static PassOwnPtrWillBeRawPtr<CustomElementUpgradeCandidateMap> create();
     virtual ~CustomElementUpgradeCandidateMap();
 
     // API for CustomElementRegistrationContext to save and take candidates
 
     typedef WillBeHeapLinkedHashSet<RawPtrWillBeWeakMember<Element> > ElementSet;
 
@@ skipping 10 matching lines @@
     virtual void elementDidFinishParsingChildren(Element*) OVERRIDE;
     void moveToEnd(Element*);
 
     typedef WillBeHeapHashMap<RawPtrWillBeWeakMember<Element>, CustomElementDescriptor> UpgradeCandidateMap;
     UpgradeCandidateMap m_upgradeCandidates;
 
     typedef WillBeHeapHashMap<CustomElementDescriptor, OwnPtrWillBeMember<ElementSet> > UnresolvedDefinitionMap;
     UnresolvedDefinitionMap m_unresolvedDefinitions;
 };
 
-}
+} // namespace blink
 
 #endif // CustomElementUpgradeCandidateMap_h