infrun.c:handle_inferior_event: Remove some more dead code.

infrun.c:handle_inferior_event: Remove some more dead code.

'ecs' is always memset before being passed to handle_inferior_event.
The stop func is only filled in later in the flow.  And since "Remove
dead sets/clears of ecs->random signal", nothing ever sets
ecs->random_signal before this part is reached either.

(Also tested with some added assertions in place.)

gdb/
2013-10-28  Pedro Alves  <palves@redhat.com>

	* infrun.c (clear_stop_func): Delete.
	(handle_inferior_event): Don't call clear_stop_func and don't
	clear 'ecs->random_signal'.