FFE: add middle button software area

[Timo Aaltonen]

I have laptops with a synaptics forcepad, and trying to use middle-button emulation on them by hitting left & right buttons is a hit-or-miss making it quite a frustrating experience.

Adding this from upstream fixes that:

commit 886b5a2cd8c785e48ddf5ceb4a902cd1f518d2a9
Author: Peter Hutterer
Date: Mon Apr 4 10:06:36 2016 +1000

    touchpad: add a middle button software area

    Middle button interaction is most commonly to paste and it is a single-event
    interaction (button press). We provided middle button in software button mode
    by emulating it with a two-finger press with L+R down at the same time. This
    is also what many touchpads are spectacularly bad at, it is very common to
    detect the physical button down event before the second finger registers,
    resulting in left or right clicks where a middle button should be triggered.

    Unless the fingers are resting on the touchpad for at least one scanout, the
    success rate for middle button emulation is only at 70% or so.

    This patch adds a 25%-width middle button area between the left and the right
    software button, everything else stays the same. To avoid immediate breakage,
    the middle button emulation remains but may be removed in the future.
    The doc is updated to only refer to the middle button area now.

    https://bugs.freedesktop.org/show_bug.cgi?id=94755

[Launchpad Janitor (janitor)]

This bug was fixed in the package libinput - 1.2.3-1ubuntu1

---------------
libinput (1.2.3-1ubuntu1) xenial; urgency=medium

  * Merge from debian.
  * touchpad-add-a-middle-button-software-area.diff: Add a software area
    for middle-button emulation. (LP: #1570282)

libinput (1.2.3-1) unstable; urgency=medium

  * New upstream release.

 -- Timo Aaltonen <email address hidden> Thu, 14 Apr 2016 13:17:43 +0300