blink: Cleanup class forward declarations

third_party/WebKit/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 23 matching lines @@
 
 #include "core/CoreExport.h"
 #include "core/frame/DOMWindowProperty.h"
 #include "core/timing/MemoryInfo.h"
 #include "core/timing/PerformanceBase.h"
 #include "core/timing/PerformanceNavigation.h"
 #include "core/timing/PerformanceTiming.h"
 
 namespace blink {
 
-class InspectorWebPerfAgent;
 class ScriptState;
 class ScriptValue;
 
 class CORE_EXPORT Performance final : public PerformanceBase,
                                       public DOMWindowProperty {
   DEFINE_WRAPPERTYPEINFO();
   USING_GARBAGE_COLLECTED_MIXIN(Performance);
   friend class PerformanceTest;
 
  public:
@@ skipping 20 matching lines @@
 
   mutable Member<PerformanceNavigation> m_navigation;
   mutable Member<PerformanceTiming> m_timing;
 
   bool m_observingLongTasks;
 };
 
 }  // namespace blink
 
 #endif  // Performance_h