Expose performance.memory in workers

Source/modules/performance/WorkerPerformance.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 23 matching lines @@
 #include "bindings/v8/ScriptWrappable.h"
 #include "core/dom/ContextLifecycleObserver.h"
 #include "platform/heap/Handle.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
 #include "wtf/RefPtr.h"
 
 namespace WebCore {
 
 class ExecutionContext;
+class MemoryInfo;
 
 class WorkerPerformance : public GarbageCollectedFinalized<WorkerPerformance>, public ScriptWrappable {
 public:
     static WorkerPerformance* create()
     {
         return new WorkerPerformance();
     }
     ~WorkerPerformance();
 
     double now(ExecutionContext*) const;
+    PassRefPtrWillBeRawPtr<MemoryInfo> memory() const;
 
     void trace(Visitor*) { }
 
 private:
     WorkerPerformance();
 };
 
 }
 
 #endif // WorkerPerformance_h