Experiment: disallow prefinalizer allocation.

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

 /*
  * 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 1245 matching lines @@
 }
 #endif
 
 void ThreadState::invokePreFinalizers() {
   ASSERT(checkThread());
   ASSERT(!sweepForbidden());
   TRACE_EVENT0("blink_gc", "ThreadState::invokePreFinalizers");
 
   SweepForbiddenScope sweepForbidden(this);
   ScriptForbiddenIfMainThreadScope scriptForbidden;
+  NoAllocationScope noAllocationScope(this);
 
   double startTime = WTF::currentTimeMS();
   if (!m_orderedPreFinalizers.isEmpty()) {
     // Call the prefinalizers in the opposite order to their registration.
     //
     // The prefinalizer callback wrapper returns |true| when its associated
     // object is unreachable garbage and the prefinalizer callback has run.
     // The registered prefinalizer entry must then be removed and deleted.
     //
     auto it = --m_orderedPreFinalizers.end();
@@ skipping 272 matching lines @@
     collectGarbage(BlinkGC::NoHeapPointersOnStack, BlinkGC::GCWithSweep,
                    BlinkGC::ForcedGC);
     size_t liveObjects = heap().heapStats().markedObjectSize();
     if (liveObjects == previousLiveObjects)
       break;
     previousLiveObjects = liveObjects;
   }
 }
 
 }  // namespace blink