PsiBuilder.Marker parseConditional(final PsiBuilder builder) {
    if (useNewImplementation) {
      return myNewExpressionParser.tryParseWithPrecedenceAtMost(builder, BasicPrattExpressionParser.CONDITIONAL_EXPR_PRECEDENCE,
                                                                FORBID_LAMBDA_MASK);
    }
    return myOldExpressionParser.parseConditional(builder, 0);
  }
PsiBuilder.Marker parseConditional(final PsiBuilder builder)