mangle.c (write_encoding): Pass write_function_type the FUNCTION_DECL for the function being encoded.

	* mangle.c (write_encoding): Pass write_function_type the
	FUNCTION_DECL for the function being encoded.
	(write_function_type): Pass it along to write_bare_function_type.
	(write_bare_function_type): Pass it along to write_method_parms.
	(write_method_parms): Don't mangle the compiler-generated
	parameters to a constructor or destructor.

From-SVN: r39985