Use OwnPtrs for heap contains cache and persistent anchor. We were leaking the HeapContainsCache.

Source/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 437 matching lines @@
 
     // Get one of the heap structures for this thread.
     //
     // The heap is split into multiple heap parts based on object
     // types. To get the index for a given type, use
     // HeapTrait<Type>::index.
     BaseHeap* heap(int index) const { return m_heaps[index]; }
 
     // Infrastructure to determine if an address is within one of the
     // address ranges for the Blink heap.
-    HeapContainsCache* heapContainsCache() { return m_heapContainsCache; }
+    HeapContainsCache* heapContainsCache() { return m_heapContainsCache.get(); }
     bool contains(Address);
     bool contains(void* pointer) { return contains(reinterpret_cast<Address>(pointer)); }
     bool contains(const void* pointer) { return contains(const_cast<void*>(pointer)); }
 
     // Finds the Blink HeapPage in this thread-specific heap
     // corresponding to a given address. Return 0 if the address is
     // not contained in any of the pages.
     BaseHeapPage* heapPageFromAddress(Address);
 
     // List of persistent roots allocated on the given thread.
-    PersistentNode* roots() const { return m_persistents; }
+    PersistentNode* roots() const { return m_persistents.get(); }
 
     // List of global persistent roots not owned by any particular thread.
     // globalRootsMutex must be acquired before any modifications.
     static PersistentNode* globalRoots();
     static Mutex& globalRootsMutex();
 
     // Visit local thread stack and trace all pointers conservatively.
     void visitStack(Visitor*);
 
     // Visit all persistents allocated on this thread.
@@ skipping 33 matching lines @@
     // We would like to manage lifetime of the ThreadState attached
     // to the main thread explicitly instead and still use normal
     // constructor and destructor for the ThreadState class.
     // For this we reserve static storage for the main ThreadState
     // and lazily construct ThreadState in it using placement new.
     static uint8_t s_mainThreadStateStorage[];
 
     void trace(Visitor*);
 
     ThreadIdentifier m_thread;
-    PersistentNode* m_persistents;
+    OwnPtr<PersistentNode> m_persistents;
     StackState m_stackState;
     intptr_t* m_startOfStack;
     intptr_t* m_endOfStack;
     void* m_safePointScopeMarker;
     Vector<Address> m_safePointStackCopy;
     bool m_atSafePoint;
     Vector<Interruptor*> m_interruptors;
     bool m_gcRequested;
     volatile int m_sweepRequested;
     bool m_sweepInProgress;
     size_t m_noAllocationCount;
     bool m_inGC;
     BaseHeap* m_heaps[NumberOfHeaps];
-    HeapContainsCache* m_heapContainsCache;
+    OwnPtr<HeapContainsCache> m_heapContainsCache;
     HeapStats m_stats;
     HeapStats m_statsAfterLastGC;
 
     Vector<OwnPtr<CleanupTask> > m_cleanupTasks;
     bool m_isCleaningUp;
 };
 
 template<ThreadAffinity affinity> class ThreadStateFor;
 
 template<> class ThreadStateFor<MainThreadOnly> {
 public:
     static ThreadState* state()
     {
         // This specialization must only be used from the main thread.
         ASSERT(ThreadState::isMainThread());
         return ThreadState::mainThreadState();
     }
 };
 
 template<> class ThreadStateFor<AnyThread> {
 public:
     static ThreadState* state() { return ThreadState::current(); }
 };
 
 }
 
 #endif // ThreadState_h