Oilpan: Remove most WillBe types from the code base

third_party/WebKit/Source/core/html/HTMLMediaSource.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 24 matching lines @@
 #include "core/html/URLRegistry.h"
 #include "platform/heap/Handle.h"
 #include "wtf/Forward.h"
 
 namespace blink {
 
 class WebMediaSource;
 class HTMLMediaElement;
 class TimeRanges;
 
-class CORE_EXPORT HTMLMediaSource : public URLRegistrable, public WillBeGarbageCollectedMixin {
+class CORE_EXPORT HTMLMediaSource : public URLRegistrable, public GarbageCollectedMixin {
 public:
     static void setRegistry(URLRegistry*);
     static HTMLMediaSource* lookup(const String& url) { return s_registry ? static_cast<HTMLMediaSource*>(s_registry->lookup(url)) : 0; }
 
 #if !ENABLE(OILPAN)
     void ref() { refHTMLMediaSource(); }
     void deref() { derefHTMLMediaSource(); }
 #endif
 
     // Called when an HTMLMediaElement is attempting to attach to this object,
@@ skipping 18 matching lines @@
     // URLRegistrable
     URLRegistry& registry() const override { return *s_registry; }
 
 private:
     static URLRegistry* s_registry;
 };
 
 } // namespace blink
 
 #endif