Experimental scanner: fix starting positions of tokens.

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 284 matching lines @@
       : ScannerBase(isolate),
         source_handle_(source),
         buffer_(NULL),
         buffer_end_(NULL),
         start_(NULL),
         cursor_(NULL),
         marker_(NULL),
         last_octal_end_(NULL) {
     ASSERT(source->IsFlat());
     SetBufferBasedOnHandle();
+    current_.beg_pos = current_.end_pos = next_.beg_pos = next_.end_pos = 0;
   }
 
   virtual void Init() {
     Scan();
   }
 
   virtual ~ExperimentalScanner() { }
 
   virtual void SeekForward(int pos);
   virtual void SetEnd(int pos);
@@ skipping 295 matching lines @@
   // character.
   const Char* temp_cursor = last_octal_end_ - 1;
   while (temp_cursor >= buffer_ && *temp_cursor >= '0' && *temp_cursor <= '7')
     --temp_cursor;
   return Location(temp_cursor - buffer_ + 1, last_octal_end_ - buffer_);
 }
 
 } }
 
 #endif  // V8_LEXER_EXPERIMENTAL_SCANNER_H