A justice or judge of the United States before whom a habeas corpus proceeding is pending, may, before final judgment or after final judgment of discharge, or pending appeal, stay any proceeding against the person detained in any State court or by or under the authority of any State for any matter involved in the habeas corpus proceeding.

After the granting of such a stay, any such proceeding in any State court or by or under the authority of any State shall be void. If no stay is granted, any such proceeding shall be as valid as if no habeas corpus proceedings or appeal were pending.