Go for a more intuitive unset behaviour of scroll method and acceleration
profile properties.
Summary:
Unsetting a scroll method should only work, if the scroll method is currently
active. For example when scroll-two-finger is active (i.e. scroll-edge,
scroll-on-button-down is not active):
* unsetting scroll-two-finger should deactivate it and activate no-scroll
* but unsetting for example scroll-edge should _not_ deactivate scroll-two-
finger and _not_ activate no-scroll
Reworked setting scroll method auto test in order to test it.
Regarding acceleration profiles: Unsetting one, should always switch to the
other possible one as long as both are supported. In this case
LIBINPUT_CONFIG_ACCEL_PROFILE_NONE is not a valid option in contrast to the
definition of the scroll method enums.
Reviewers: #kwin
Subscribers: plasma-devel, kwin
Tags: #kwin
Differential Revision: https://phabricator.kde.org/D3590
fd07b1dc98