Remove forward declarations from Source/core/dom/custom

Source/core/dom/custom/CustomElementScheduler.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:
  *
  * 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
@@ skipping 27 matching lines @@
 #include "wtf/OwnPtr.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/text/AtomicString.h"
 
 namespace blink {
 
 class CustomElementDescriptor;
 class CustomElementMicrotaskImportStep;
 class CustomElementMicrotaskStep;
 class CustomElementRegistrationContext;
-class Document;
-class Element;
 class HTMLImportChild;
 
 class CustomElementScheduler FINAL : public NoBaseWillBeGarbageCollected<CustomElementScheduler> {
     DECLARE_EMPTY_DESTRUCTOR_WILL_BE_REMOVED(CustomElementScheduler);
 public:
 
     static void scheduleCallback(PassRefPtr<CustomElementLifecycleCallbacks>, PassRefPtrWillBeRawPtr<Element>, CustomElementLifecycleCallbacks::CallbackType);
     static void scheduleAttributeChangedCallback(PassRefPtr<CustomElementLifecycleCallbacks>, PassRefPtrWillBeRawPtr<Element>, const AtomicString& name, const AtomicString& oldValue, const AtomicString& newValue);
 
     static void resolveOrScheduleResolution(PassRefPtrWillBeRawPtr<CustomElementRegistrationContext>, PassRefPtrWillBeRawPtr<Element>, const CustomElementDescriptor&);
     static CustomElementMicrotaskImportStep* scheduleImport(HTMLImportChild*);
 
     static void microtaskDispatcherDidFinish();
     static void callbackDispatcherDidFinish();
 
 private:
     CustomElementScheduler() { }
 
     static void enqueueMicrotaskStep(Document&, PassOwnPtrWillBeRawPtr<CustomElementMicrotaskStep>, bool importIsSync = true);
 };
 
-}
+} // namespace blink
 
 #endif // CustomElementScheduler_h