* win32-low.c (do_initial_child_stuff): Add process handle

	* win32-low.c (do_initial_child_stuff): Add process handle
	parameter.  Set current_process_handle and current_process_id from the
	parameters. Clear globals.
	(win32_create_inferior): Don't set current_process_handle and
	current_process_id here.  Instead pass them on the call to
	do_initial_child_stuff.
	(win32_attach): Likewise.
	(win32_clear_inferiors): New.
	(win32_kill): Don't close the current process handle or the
	current thread handle here.  Instead call win32_clear_inferiors.
	(win32_detach): Don't open a new handle to the process.  Call
	win32_clear_inferiors.
	(win32_join): Don't rely on current_process_handle; open a new
	handle using the process id.
	(win32_wait): Call win32_clear_inferiors when the inferior process
	has exited.