patch 9.0.1231: completion of :runtime does not handle {where} argument

Problem:    Completion of :runtime does not handle {where} argument.
Solution:   Parse the {where} argument. (closes #11863)
diff --git a/src/filepath.c b/src/filepath.c
index be1a581..c448edb 100644
--- a/src/filepath.c
+++ b/src/filepath.c
@@ -1388,7 +1388,7 @@
     if (file != NULL && !error)
     {
 	ga_init2(&ga, sizeof(char_u *), 10);
-	globpath(tv_get_string(&argvars[0]), file, &ga, flags);
+	globpath(tv_get_string(&argvars[0]), file, &ga, flags, FALSE);
 	if (rettv->v_type == VAR_STRING)
 	    rettv->vval.v_string = ga_concat_strings(&ga, "\n");
 	else if (rettv_list_alloc(rettv) == OK)