atspi: do operation if its object is available

atspi: do operation if its object is available

Operation 1. activate
An object under the naviframe item is accessible even though new naviframe item
is pushed on it. In this case, it is possilbe to do action of the object.
So this patch set is checking SHOWING state before doing action.

Operation 2. selection
It was possible to (de)select even though its one of perent freezes events.
It is impossilbe to (de)select using touch event if freeze_events set to 1.
So it should work same using atspi interface.

TODO: handle non UI action

Change-Id: I59d69cd117252ef7364fd80536ce6b153c0ce920