Check if display exists in RootTDAOrganizer

There's a scenario that the display is removed before DAOrganizer callbacks
propagate to the client side.
This CL checks if the display still exists before applying
 DisplayAreaInfo changes.

Test: manual - repro steps in bug
fixes: 182790285

Change-Id: I1180ca6bea4e5bd87f22298483400c9d604bae06
1 file changed