Experimental scanner fix: recognize one byte strings inside utf16 files.

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 145 matching lines @@
     return current_literal_->utf16_string;
   }
 
   int literal_length() {
     if (!current_literal_->Valid(current_.beg_pos)) {
       FillLiteral(current_, current_literal_);
     }
     return current_literal_->length;
   }
 
+  // This should be is_onebyte or is_latin1; it doesn't mean ASCII for real.
   bool is_literal_ascii() {
     if (!current_literal_->Valid(current_.beg_pos)) {
       FillLiteral(current_, current_literal_);
     }
     return current_literal_->is_ascii;
   }
 
   bool is_literal_contextual_keyword(Vector<const char> keyword) {
     if (!is_literal_ascii()) return false;
     Vector<const char> literal = literal_ascii_string();
@@ skipping 426 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