* tests/glr-regr1.at (Badly Collapsed GLR States): Prototype yylex

and yyerror.
Have yyerror `use' its arguments.
* tests/calc.at (AT_CHECK_PUSHDEFS): AT_YYERROR_SEES_LOC_IF
returns true when location & yacc & pure & parse-param.
(_AT_DATA_CALC_Y): Let yyerror ``use'' its arguments.