Replaced ptrdiff_t with std::ptrdiff_t in all files to enable build with gcc-4.6.0.

third_party/tcmalloc/chromium/src/symbolize.h

 // Copyright (c) 2009, 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 17 matching lines @@
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 // ---
 // Author: Craig Silverstein
 
 #ifndef TCMALLOC_SYMBOLIZE_H_
 #define TCMALLOC_SYMBOLIZE_H_
 
 #include "config.h"
 #ifdef HAVE_STDINT_H
+#include <stddef.h>
 #include <stdint.h>  // for uintptr_t
 #endif
 #include <map>
 
 using std::map;
 
 // SymbolTable encapsulates the address operations necessary for stack trace
 // symbolization. A common use-case is to Add() the addresses from one or
 // several stack traces to a table, call Symbolize() once and use GetSymbol()
 // to get the symbol names for pretty-printing the stack traces.
@@ skipping 25 matching lines @@
   static const int kSymbolSize = 1024;
 
   // Map from addresses to symbol names.
   SymbolMap symbolization_table_;
 
   // Pointer to the buffer that stores the symbol names.
   char *symbol_buffer_;
 };
 
 #endif  // TCMALLOC_SYMBOLIZE_H_