Experimental scanner: save all token data into one vector.

src/lexer/experimental-scanner.h

 // Copyright 2013 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 36 matching lines @@
     bool IsValid() const {
       return beg_pos >= 0 && end_pos >= beg_pos;
     }
 
     static Location invalid() { return Location(-1, -1); }
 
     int beg_pos;
     int end_pos;
   };
 
+  struct SavedToken {
+    int beg, end;
+    Token::Value value;
+  };
+
   ExperimentalScanner(const char* fname,
                       bool read_all_at_once,
                       Isolate* isolate);
   ~ExperimentalScanner();
 
   Token::Value Next();
   Token::Value current_token();
   Location location();
 
   void Record(v8::internal::Token::Value token, int beg_pos, int end_pos);
 
  private:
   void FillTokens();
   static const int BUFFER_SIZE = 256;
-  std::vector<v8::internal::Token::Value> token_;
-  std::vector<int> beg_;
-  std::vector<int> end_;
+  std::vector<SavedToken> token_;
   size_t current_;
   size_t fetched_;
   FILE* file_;
   PushScanner* scanner_;
   bool read_all_at_once_;
   const v8::internal::byte* source_;
   int length_;
 };
 
 } }  // namespace v8::internal
 
 #endif