Fix TryCatch.ReThrow() to not clobber Message.

include/v8.h

 // Copyright 2012 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 4715 matching lines @@
  private:
   // Make it hard to create heap-allocated TryCatch blocks.
   TryCatch(const TryCatch&);
   void operator=(const TryCatch&);
   void* operator new(size_t size);
   void operator delete(void*, size_t);
 
   v8::internal::Isolate* isolate_;
   void* next_;
   void* exception_;
-  void* message_;
+  void* message_obj_;
+  void* message_script_;
+  int message_start_pos_;
+  int message_end_pos_;
   bool is_verbose_ : 1;
   bool can_continue_ : 1;
   bool capture_message_ : 1;
   bool rethrow_ : 1;
   bool has_terminated_ : 1;
 
   friend class v8::internal::Isolate;
 };
 
 
@@ skipping 1564 matching lines @@
 
 
 }  // namespace v8
 
 
 #undef V8EXPORT
 #undef TYPE_CHECK
 
 
 #endif  // V8_H_