Disable collection backing reallocation during pre finalizer

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

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef HeapAllocator_h
 #define HeapAllocator_h
 
 #include "platform/heap/Heap.h"
 #include "platform/heap/Persistent.h"
 #include "platform/heap/TraceTraits.h"
@@ skipping 133 matching lines @@
     ASSERT_NOT_REACHED();
     return 0;
   }
 
   static void DeleteArray(void* ptr) { ASSERT_NOT_REACHED(); }
 
   static bool IsAllocationAllowed() {
     return ThreadState::Current()->IsAllocationAllowed();
   }
 
+  static bool IsBackingReallocationAllowed() {

[kouhei (in TOK), 2017/04/12 06:14:01]

Can we make it clear that this is inside prefinalizer so that we can use the
predicate in DCHECKs to assert certain methods are not called from prefinalizer.

[haraken, 2017/04/12 06:44:34]

Maybe we can rename this to IsObjectRessurectionForbidden.

I cannot come up with a better name...

[keishi, 2017/04/12 09:43:53]

Done.

+    return ThreadState::Current()->IsBackingReallocationAllowed();
+  }
+
   template <typename T>
   static bool IsHeapObjectAlive(T* object) {
     return ThreadHeap::IsHeapObjectAlive(object);
   }
 
   template <typename VisitorDispatcher>
   static void MarkNoTracing(VisitorDispatcher visitor, const void* t) {
     visitor->MarkNoTracing(t);
   }
 
@@ skipping 678 matching lines @@
     const blink::HeapHashCountedSet<Value, HashFunctions, Traits>& set,
     VectorType& vector) {
   CopyToVector(static_cast<const HashCountedSet<Value, HashFunctions, Traits,
                                                 blink::HeapAllocator>&>(set),
                vector);
 }
 
 }  // namespace WTF
 
 #endif