Revisit scrolling settings, Stretch edition

It seems that 3.0~alpha1 does natural scrolling by default, while we decided two years ago (#7779 (closed)) to not do that.

Our custom settings live in config/chroot_local-includes/etc/dconf/db/local.d/00_Tails_defaults, but the way we do it may be obsolete in feature/stretch, as these settings have moved from org/gnome/settings-daemon/peripherals/touchpad to org/gnome/desktop/peripherals/touchpad. Which suggests that on Stretch, GNOME now enables natural scrolling by default.

We should update our survey of what other OS’es do with more recent info + info about scrolling settings, and decide how we want Tails 3.0 to behave.

During our December monthly meeting [1] we discussed this and decided to rather drop our customisation (as most of the OS are doing natural scrolling now) and let GNOME+libinput do what they think is best, i.e. natural scrolling in most cases.

This way we keep reducing our delta with upstream.

[1]https://tails.boum.org/contribute/meetings/201612/

Blueprint: https://tails.boum.org/blueprint/touchpad/

Related issues

• Related to #7779 (closed)
• Related to #11993 (closed)

Original created by @intrigeri on 11969 (Redmine)