* cp-tree.h (cxx_saved_binding): Declare.
(struct saved_scope): Adjust type of field 'old_binding'.
* decl.c (cxx_saved_binding_make): New macro.
(struct cxx_saved_binding): Define.
(store_bindings): Adjust prototype. Use cxx_saved_binding to save
C++ bindings.
(maybe_push_to_top_level): Adjust local variable type.
(pop_from_top_level): Likewise.