[cleanup] Remove unused PreParser factory method

R=nikolaos@chromium.org

Review-Url: https://codereview.chromium.org/2316373006
Cr-Commit-Position: refs/heads/master@{#39316}

src/parsing/preparser.h

@@ -462,11 +462,6 @@ class PreParserFactory {
                                        int pos) {
     return PreParserExpression::Default();
   }
-  PreParserExpression NewArrayLiteral(PreParserExpressionList values,
-                                      int literal_index,
-                                      int pos) {
-    return PreParserExpression::ArrayLiteral();
-  }
   PreParserExpression NewArrayLiteral(PreParserExpressionList values,
                                       int first_spread_index, int literal_index,
                                       int pos) {