Remove ThreadHeap::m_threads

third_party/WebKit/Source/platform/heap/ThreadState.h

Index: third_party/WebKit/Source/platform/heap/ThreadState.h
diff --git a/third_party/WebKit/Source/platform/heap/ThreadState.h b/third_party/WebKit/Source/platform/heap/ThreadState.h
index 82c9934c2e3f2b3ed0e776c1319bdde581804633..5595215ee66060b19f77ee01919e4743f1ea328e 100644
--- a/third_party/WebKit/Source/platform/heap/ThreadState.h
+++ b/third_party/WebKit/Source/platform/heap/ThreadState.h
@@ -160,9 +160,6 @@ class PLATFORM_EXPORT ThreadState {
     ThreadState* m_state;
   };
 
-  void lockThreadAttachMutex();
-  void unlockThreadAttachMutex();
-
   static void attachMainThread();
 
   // Associate ThreadState object with the current thread. After this
@@ -611,7 +608,6 @@ class PLATFORM_EXPORT ThreadState {
 
   void reportMemoryToV8();
 
-  // Should only be called under protection of threadAttachMutex().
   const Vector<std::unique_ptr<BlinkGCInterruptor>>& interruptors() const {
     return m_interruptors;
   }
@@ -630,7 +626,7 @@ class PLATFORM_EXPORT ThreadState {
   // and lazily construct ThreadState in it using placement new.
   static uint8_t s_mainThreadStateStorage[];
 
-  ThreadHeap* m_heap;
+  std::unique_ptr<ThreadHeap> m_heap;
   ThreadIdentifier m_thread;
   std::unique_ptr<PersistentRegion> m_persistentRegion;
   BlinkGC::StackState m_stackState;