DR 1402
	PR c++/53733
	* cp-tree.h (FNDECL_SUPPRESS_IMPLICIT_DECL): New.
	(struct lang_decl_fn): Add suppress_implicit_decl field.
	* method.c (implicitly_declare_fn): Check it.
	(process_subob_fn): Add no_implicit_p parm.
	(walk_field_subobs, synthesized_method_walk): Likewise.
	(maybe_explain_implicit_delete): Adjust.
	(explain_implicit_non_constexpr): Adjust.

From-SVN: r189396