Fix copy-on-write assert by setting the new array map early.

src/heap-inl.h

 // Copyright 2006-2008 the V8 project authors. 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
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 41 matching lines @@
 
 Object* Heap::AllocateSymbol(Vector<const char> str,
                              int chars,
                              uint32_t hash_field) {
   unibrow::Utf8InputBuffer<> buffer(str.start(),
                                     static_cast<unsigned>(str.length()));
   return AllocateInternalSymbol(&buffer, chars, hash_field);
 }
 
 
+Object* Heap::CopyFixedArray(FixedArray* src) {
+  return CopyFixedArrayWithMap(src, src->map());
+}
+
+
 Object* Heap::AllocateRaw(int size_in_bytes,
                           AllocationSpace space,
                           AllocationSpace retry_space) {
   ASSERT(allocation_allowed_ && gc_state_ == NOT_IN_GC);
   ASSERT(space != NEW_SPACE ||
          retry_space == OLD_POINTER_SPACE ||
          retry_space == OLD_DATA_SPACE ||
          retry_space == LO_SPACE);
 #ifdef DEBUG
   if (FLAG_gc_interval >= 0 &&
@@ skipping 423 matching lines @@
 
 
 void ExternalStringTable::ShrinkNewStrings(int position) {
   new_space_strings_.Rewind(position);
   Verify();
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_INL_H_