Delayed event UI update

[fb71]

Seem sthat after changing (c5d8632d8689dfc86e3339f415d57a7439067cbd (#5)) DefaultAppDesign delayed events are not always handled properly. Sometimes the UI does not get updated. Seems that there is a race condition.

[fb71]

Nasty bug! Glad to fix it :)

[fb71]

There are two situations where UICallback is necessary:

• 1.) there are events in the queue and there are display=true handlers
• 2.) or there are delay>0 and display=true handlers

For 1.) there is/was a RAP PhaseListener. Which was non-functional since porting to polymap4.

For 2.) DeferringListeners tryed to manage this with SessionUICallbackCounter but this has a race condition as the activation of the UI callback is done in the event DispatcherThread when the Display thread may already has return to the client

[fb71]

Both removed. UICallback always is enabled. Until we have a stable solution.