* call.c (build_new_method_call_1): Use constructo_name to get
	ctor name.  Move argument processing earlier to merge cdtor
	handling blocks.
	* decl.c (grokfndecl): Cdtors have special names.
	* method.c (implicitly_declare_fn): Likewise. Simplify flag setting.
	* pt.c (check_explicit_specialization): Cdtor name is already
	special.
	* search.c (class_method_index_for_fn): Likewise.

	* g++.dg/plugin/decl-plugin-test.C: Expect special ctor name.

From-SVN: r249838