Switch to using AB overlay in stage activity.
Revert "Switch to using AB overlay in stage activity."

This reverts commit a4cd51e46c5d0952b5618e7cc8455345f4291cfb.
Fix display of props in stage view.
Fix multi-touch interaction in stage view.
Fix name of method.
Discard touch and fix display of stage in thumb mode.
Only drop prop click once touch leaves hit area.