Merge "stagefright: MPEG4Writer: fix Integer overflow"

    mOwner->beginBox("ctts");

    mOwner->writeInt32(0);  // version=0, flags=0

    uint32_t delta = mMinCttsOffsetTimeUs - getStartTimeOffsetScaledTime();

    int64_t delta = mMinCttsOffsetTimeUs - getStartTimeOffsetScaledTime();

    mCttsTableEntries->adjustEntries([delta](size_t /* ix */, uint32_t (&value)[2]) {

        // entries are <count, ctts> pairs; adjust only ctts

        uint32_t duration = htonl(value[1]); // back to host byte order

        value[1] = htonl(duration - delta);

        // Prevent overflow and underflow

        if (delta > duration) {

            duration = 0;

        } else if (delta < 0 && UINT32_MAX + delta < duration) {

            duration = UINT32_MAX;

        } else {

            duration -= delta;

        }

        value[1] = htonl(duration);

    });

    mCttsTableEntries->write(mOwner);

    mOwner->endBox();  // ctts