gcc/
	* tree.h (vec_member): Declare.
	* tree.c (vec_member): Define.

gcc/cp/
	* name-lookup.c (struct arg_lookup): Convert namespaces and
	classes fields to VEC.
	(arg_assoc_namespace): Adjust for new type of namespaces.
	(arg_assoc_class): Adjust for new type of classes.
	(lookup_arg_dependent): Use make_tree_vector and
	release_tree_vector.
	* typeck2.c (build_x_arrow): Use vec_member.

From-SVN: r160936