Comment 2 for bug 897131

Within the attached archive are the outputs from evtest and xev for the two issues I described.
For evtest-chord.out and xev-chord.out, I did this:

button-1 down
button-2 down
button-2 up
button-1 up

For evtest-middle-motion.out and xev-middle-motion.out, I did this:

button-2 down
wiggle touchpoint
button-2 up

As you can see, xev shows that the underlying device is reporting all
the events perfectly. Somewhere else in the input stack, the events
are being converted (lost in the former case, converted into button-5
presses aka scroll events in the latter)