Fix Windows build.

src/heap.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 1085 matching lines @@
   static const int kInitialSymbolTableSize = 2048;
   static const int kInitialEvalCacheSize = 64;
 
   friend class Factory;
   friend class DisallowAllocationFailure;
   friend class AlwaysAllocateScope;
   friend class LinearAllocationScope;
 };
 
 
-struct HeapStats {
+class HeapStats {
+ public:
   int new_space_size;
   int new_space_capacity;
   int old_pointer_space_size;
   int old_pointer_space_capacity;
   int old_data_space_size;
   int old_data_space_capacity;
   int code_space_size;
   int code_space_capacity;
   int map_space_size;
   int map_space_capacity;
@@ skipping 499 matching lines @@
   }
   static TranscendentalCache* caches_[kNumberOfCaches];
   Element elements_[kCacheSize];
   Type type_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_H_