(build_opfncall): Use DECL_CHAIN, not TREE_CHAIN for results from
lookup_fnfields.  Always give warning/error on bad code.
(build_overload_int): New routine.  Break out functionality from
build_overload_value so we can reuse it.
(build_overload_value): Handle pointer to member functions as value parameters
for templates.
(build_overload_identifier): Since template parameters are shared
among all instantiations, we have to substitute in the real types in
TREE_TYPE (parm).

From-SVN: r10045