Oilpan: Remove most WillBe types from the code base

third_party/WebKit/Source/core/loader/WorkerThreadableLoader.h

 /*
  * Copyright (C) 2009 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 176 matching lines @@
         // on the main thread only before |m_loaderDoneEvent| is signaled and can be read
         // on the worker context thread only after |m_loaderDoneEvent| is signaled.
         Vector<OwnPtr<ExecutionContextTask>> m_clientTasks;
         Mutex m_lock;
     };
 
     WorkerThreadableLoader(WorkerGlobalScope&, ThreadableLoaderClient*, const ResourceRequest&, const ThreadableLoaderOptions&, const ResourceLoaderOptions&, BlockingBehavior);
 
     void didReceiveResourceTiming(const ResourceTimingInfo&) override;
 
-    RefPtrWillBePersistent<WorkerGlobalScope> m_workerGlobalScope;
+    Persistent<WorkerGlobalScope> m_workerGlobalScope;
     RefPtr<ThreadableLoaderClientWrapper> m_workerClientWrapper;
 
     MainThreadBridgeBase* m_bridge;
 };
 
 } // namespace blink
 
 #endif // WorkerThreadableLoader_h