Keep (Heap)TerminatedArray in a consistent state while building.

third_party/WebKit/Source/platform/heap/HeapTest.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 4325 matching lines @@
     IntWrapper::s_destructorCalls = 0;
 
     HeapTerminatedArray<TerminatedArrayItem>* arr = 0;
 
     const size_t prefixSize = 4;
     const size_t suffixSize = 4;
 
     {
         HeapTerminatedArrayBuilder<TerminatedArrayItem> builder(arr);
         builder.grow(prefixSize);
+        conservativelyCollectGarbage();
         for (size_t i = 0; i < prefixSize; i++)
             builder.append(TerminatedArrayItem(IntWrapper::create(i)));
         arr = builder.release();
     }
 
     conservativelyCollectGarbage();
     EXPECT_EQ(0, IntWrapper::s_destructorCalls);
     EXPECT_EQ(prefixSize, arr->size());
     for (size_t i = 0; i < prefixSize; i++)
         EXPECT_EQ(i, static_cast<size_t>(arr->at(i).payload()->value()));
@@ skipping 2168 matching lines @@
     EXPECT_EQ(1u, vector2.size());
 // TODO(Oilpan): when Vector.h's contiguous container support no longer disables
 // Vector<>s with inline capacity, remove.
 #if !defined(ANNOTATE_CONTIGUOUS_CONTAINER)
     EXPECT_EQ(16u, vector1.capacity());
     EXPECT_EQ(16u, vector2.capacity());
 #endif
 }
 
 } // namespace blink