Correctly update the source of recurring subtree change accessibility events.

        public void runOrPost(View source) {

            if (mSource != null) {

                mSource = getCommonPredecessor(mSource, source);

                // If there is no common predecessor, then mSource points to

                // a removed view, hence in this case always prefer the source.

                View predecessor = getCommonPredecessor(mSource, source);

                mSource = (predecessor != null) ? predecessor : source;

                return;

            }

            mSource = source;

            final long timeSinceLastMillis = SystemClock.uptimeMillis() - mLastEventTimeMillis;

            final long minEventIntevalMillis =

                    ViewConfiguration.getSendRecurringAccessibilityEventsInterval();

            mSource.removeCallbacks(this);

            if (timeSinceLastMillis >= minEventIntevalMillis) {

                mSource.removeCallbacks(this);

                run();

            } else {

                mSource.postDelayed(this, minEventIntevalMillis - timeSinceLastMillis);