* linux-low.c (linux_kill_one_lwp): Assume the lwp is stopped.

	* linux-low.c (linux_kill_one_lwp): Assume the lwp is stopped.
	(linux_kill): Stop all lwps here.  Don't delete the main lwp here.
	(linux_detach_one_lwp): Assume the lwp is stopped.
	(any_thread_of): Delete.
	(linux_detach): Stop all lwps here.  Don't blindly delete all
	breakpoints.
	(delete_lwp_callback): New.
	(linux_mourn): Delete all lwps of the process that is gone.
	(linux_wait_1): Don't delete the last lwp of the process here.
	* mem-break.h (mark_breakpoints_out): Declare.
	* mem-break.c (mark_breakpoints_out): New.
	(free_all_breakpoints): Use it.
	* server.c (handle_target_event): If the process is gone, mark
	breakpoints out.
	* thread-db.c (struct thread_db) <create_bp>: New field.
	(thread_db_enable_reporting): Fix prototype.  Store a thread event
	breakpoint reference in the thread_db struct.
	(thread_db_load_search): Clear the thread_db object.
	(try_thread_db_load_1): Ditto.
	(switch_to_process): New.
	(disable_thread_event_reporting): Use it.
	(remove_thread_event_breakpoints): New.
	(thread_db_detach, thread_db_mourn): Use it.