Fixing binary compatibility issue with new protected method.

Author: martingd

Diff for: shared/src/main/scala/scala/util/parsing/combinator/lexical/StdLexical.scala

@@ -49,7 +49,7 @@ class StdLexical extends Lexical with StdTokens {
   def identChar = letter | elem('_')
 
   /** Parses the final quote of a string literal or fails if it is unterminated. */
-  protected def stringEnd(quoteChar: Char, chars: List[Char]): Parser[Token] = {
+  private def stringEnd(quoteChar: Char, chars: List[Char]): Parser[Token] = {
     { elem(quoteChar) ^^^ StringLit(chars mkString "") } | err("unclosed string literal")
   }