Revert "Recompute the mNextFrameStartUnstuffed on every frame"

This reverts commit 89434a2523f06f7e2bb2bcc1497aebb52567b66d.

Reason for revert: regression uibench_deadline_missed-mean

Change-Id: I122cc2f42411342cc6945f0bd85106f31dd8977b
1 file changed