[heap] Fix verification of unsafe object layout changes.

src/heap/heap-inl.h

 // Copyright 2012 the V8 project 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 V8_HEAP_HEAP_INL_H_
 #define V8_HEAP_HEAP_INL_H_
 
 #include <cmath>
 
 #include "src/base/platform/platform.h"
@@ skipping 217 matching lines @@
   int size = SeqOneByteString::SizeFor(str.length());
 
   // Allocate string.
   HeapObject* result = nullptr;
   {
     AllocationResult allocation = AllocateRaw(size, OLD_SPACE);
     if (!allocation.To(&result)) return allocation;
   }
 
   // String maps are all immortal immovable objects.
-  result->set_map_no_write_barrier(map);
+  result->set_map_after_allocation(map, SKIP_WRITE_BARRIER);
   // Set length and hash fields of the allocated string.
   String* answer = String::cast(result);
   answer->set_length(str.length());
   answer->set_hash_field(hash_field);
 
   DCHECK_EQ(size, answer->Size());
 
   // Fill in the characters.
   MemCopy(answer->address() + SeqOneByteString::kHeaderSize, str.start(),
           str.length());
@@ skipping 10 matching lines @@
   Map* map = internalized_string_map();
   int size = SeqTwoByteString::SizeFor(str.length());
 
   // Allocate string.
   HeapObject* result = nullptr;
   {
     AllocationResult allocation = AllocateRaw(size, OLD_SPACE);
     if (!allocation.To(&result)) return allocation;
   }
 
-  result->set_map(map);
+  result->set_map_after_allocation(map);
   // Set length and hash fields of the allocated string.
   String* answer = String::cast(result);
   answer->set_length(str.length());
   answer->set_hash_field(hash_field);
 
   DCHECK_EQ(size, answer->Size());
 
   // Fill in the characters.
   MemCopy(answer->address() + SeqTwoByteString::kHeaderSize, str.start(),
           str.length() * kUC16Size);
@@ skipping 603 matching lines @@
 void VerifySmisVisitor::VisitRootPointers(Root root, Object** start,
                                           Object** end) {
   for (Object** current = start; current < end; current++) {
     CHECK((*current)->IsSmi());
   }
 }
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_HEAP_INL_H_