mpeg2ts: keep the size of the sync points at most 5mb per a track

    if (event.isInit()) {

        for (size_t i = 0; i < mSourceImpls.size(); ++i) {

            if (mSourceImpls[i].get() == event.getMediaSource().get()) {

                mSyncPoints.editItemAt(i).add(

                        event.getTimeUs(), event.getOffset());

                KeyedVector<int64_t, off64_t> *syncPoints = &mSyncPoints.editItemAt(i);

                syncPoints->add(event.getTimeUs(), event.getOffset());

                // We're keeping the size of the sync points at most 5mb per a track.

                size_t size = syncPoints->size();

                if (size >= 327680) {

                    int64_t firstTimeUs = syncPoints->keyAt(0);

                    int64_t lastTimeUs = syncPoints->keyAt(size - 1);

                    if (event.getTimeUs() - firstTimeUs > lastTimeUs - event.getTimeUs()) {

                        syncPoints->removeItemsAt(0, 4096);

                    } else {

                        syncPoints->removeItemsAt(size - 4096, 4096);

                    }

                }

                break;

            }

        }