Fix a crash on uninitialized ECS->EVENT_THREAD for a newly found thread.

	Fix a crash on uninitialized ECS->EVENT_THREAD for a newly found thread.
	* infrun.c (wait_for_inferior): Move this ECS->EVENT_THREAD
	initialization ...
	(fetch_inferior_event): ... and this ECS->EVENT_THREAD initialization
	...
	(handle_inferior_event): ... here after the add_thread call together
	with the local adjust_pc_after_break and reinit_frame_cache calls.