Merge "Use bitwise operator to remove pointers"

    std::for_each(windows.begin(), windows.end(), [&allPilferedPointerIds](TouchedWindow& w) {

        std::bitset<MAX_POINTER_ID + 1> pilferedByOtherWindows =

                w.pilferedPointerIds ^ allPilferedPointerIds;

        // TODO(b/211379801) : convert pointerIds to use std::bitset, which would allow us to

        // replace the loop below with a bitwise operation. Currently, the XOR operation above is

        // redundant, but is done to make the code more explicit / easier to convert later.

        for (std::size_t i = 0; i < pilferedByOtherWindows.size(); i++) {

            if (pilferedByOtherWindows.test(i) && !w.pilferedPointerIds.test(i)) {

                // Pointer is pilfered by other windows, but not by this one! Remove it from here.

                // We could call 'removeTouchedPointerFromWindow' here, but it's faster to directly

                // manipulate it.

                w.pointerIds.reset(i);

            }

        }

        w.pointerIds &= ~pilferedByOtherWindows;

    });

    std::erase_if(windows, [](const TouchedWindow& w) { return w.pointerIds.none(); });

}