Clean up forward declarations in Source/core

Source/core/timing/Performance.h

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  * Copyright (C) 2012 Intel 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.
@@ skipping 30 matching lines @@
 #include "platform/heap/Handle.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
 #include "wtf/RefPtr.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink {
 
 class Document;
 class ExceptionState;
-class ResourceRequest;
-class ResourceResponse;
 class ResourceTimingInfo;
 class UserTiming;
 
 using PerformanceEntryVector = WillBeHeapVector<RefPtrWillBeMember<PerformanceEntry>>;
 
 class Performance final : public RefCountedWillBeGarbageCollectedFinalized<Performance>, public DOMWindowProperty, public EventTargetWithInlineData {
     DEFINE_WRAPPERTYPEINFO();
     REFCOUNTED_EVENT_TARGET(Performance);
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(Performance);
 public:
@@ skipping 42 matching lines @@
     PerformanceEntryVector m_resourceTimingBuffer;
     unsigned m_resourceTimingBufferSize;
     double m_referenceTime;
 
     RefPtrWillBeMember<UserTiming> m_userTiming;
 };
 
 } // namespace blink
 
 #endif // Performance_h