Oilpan: Remove most WillBe types from the code base

third_party/WebKit/Source/modules/filesystem/FileWriterBase.h

 /*
  * Copyright (C) 2010 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 21 matching lines @@
 #define FileWriterBase_h
 
 #include "platform/heap/Handle.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
 
 namespace blink {
 
 class WebFileWriter;
 
-class FileWriterBase : public RefCountedGarbageCollectedWillBeNoBase<FileWriterBase>, public WillBeGarbageCollectedMixin {
+class FileWriterBase : public GarbageCollectedMixin {
 public:
     virtual ~FileWriterBase();
     void initialize(PassOwnPtr<WebFileWriter>, long long length);
 
     long long position() const
     {
         return m_position;
     }
     long long length() const
     {
@@ skipping 24 matching lines @@
 
 private:
     OwnPtr<WebFileWriter> m_writer;
     long long m_position;
     long long m_length;
 };
 
 } // namespace blink
 
 #endif // FileWriterBase_h