c-common.c: Include intl.h.

c-common.c: Include intl.h.

	* c-common.c: Include intl.h.
	(shadow_warning): Rewrite to allow better diagnostic translations.
	* c-common.h: Update prototype of shadow_warning.  Declare sw_kind enum.
	* c-decl.c (warn_if_shadowing): Update calls to shadow_warning;
	use it throughout.
	* Makefile.in (c-common.o): Add intl.h.
cp:
	* decl.c: Update calls to shadow_warning.
po:
	* gcc.pot: Regenerate.

From-SVN: r64699