Simplify the shutdown sequence of Oilpan's heap

third_party/WebKit/Source/platform/heap/ThreadState.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 168 matching lines @@
     using AttachedThreadStateSet = HashSet<ThreadState*>;
     static AttachedThreadStateSet& attachedThreads();
     static RecursiveMutex& threadAttachMutex();
     static void lockThreadAttachMutex();
     static void unlockThreadAttachMutex();
 
     // Initialize threading infrastructure. Should be called from the main
     // thread.
     static void init();
     static void shutdown();
-    static void shutdownHeapIfNecessary();
     bool isTerminating() { return m_isTerminating; }
 
     static void attachMainThread();
     static void detachMainThread();
 
     // Trace all persistent roots, called when marking the managed heap objects.
     static void visitPersistentRoots(Visitor*);
 
     // Trace all objects found on the stack, used when doing conservative GCs.
     static void visitStackRoots(Visitor*);
@@ skipping 512 matching lines @@
 
 template<> class ThreadStateFor<AnyThread> {
     STATIC_ONLY(ThreadStateFor);
 public:
     static ThreadState* state() { return ThreadState::current(); }
 };
 
 } // namespace blink
 
 #endif // ThreadState_h