Revert of Large heap collection type hits assertion in Heap::allocationSizeFromSize

third_party/WebKit/Source/platform/heap/Heap.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 198 matching lines @@
     static bool popAndInvokeGlobalWeakCallback(Visitor*);
 
     // Register an ephemeron table for fixed-point iteration.
     static void registerWeakTable(void* containerObject, EphemeronCallback, EphemeronCallback);
 #if ENABLE(ASSERT)
     static bool weakTableRegistered(const void*);
 #endif
 
     static inline size_t allocationSizeFromSize(size_t size)
     {
+        // Check the size before computing the actual allocation size.  The
+        // allocation size calculation can overflow for large sizes and the check
+        // therefore has to happen before any calculation on the size.
+        RELEASE_ASSERT(size < maxHeapObjectSize);
+
         // Add space for header.
         size_t allocationSize = size + sizeof(HeapObjectHeader);
-        // The allocation size calculation can overflow for large sizes.
-        RELEASE_ASSERT(allocationSize > size);
         // Align size with allocation granularity.
         allocationSize = (allocationSize + allocationMask) & ~allocationMask;
         return allocationSize;
     }
     static Address allocateOnArenaIndex(ThreadState*, size_t, int arenaIndex, size_t gcInfoIndex, const char* typeName);
     template<typename T> static Address allocate(size_t, bool eagerlySweep = false);
     template<typename T> static Address reallocate(void* previous, size_t);
 
     static const char* gcReasonString(BlinkGC::GCReason);
     static void collectGarbage(BlinkGC::StackState, BlinkGC::GCType, BlinkGC::GCReason);
@@ skipping 294 matching lines @@
 void VisitorHelper<Derived>::handleWeakCell(Visitor* self, void* object)
 {
     T** cell = reinterpret_cast<T**>(object);
     if (*cell && !ObjectAliveTrait<T>::isHeapObjectAlive(*cell))
         *cell = nullptr;
 }
 
 } // namespace blink
 
 #endif // Heap_h