All pointer a11y is a fabrication of Clutter backend-independent
code, with the help of a ClutterVirtualInputDevice and with some
UI on top.
On the other hand, MetaInputSettings is a backend implementation
detail, this has 2 gotchas:
- In the native backend, the MetaInputSettings (and pointer a11y
with it) are initialized early, before the ClutterSeat core
pointer is set up.
- Doing this from the MetaInputSettings also means another dubious
access from the input thread into main thread territory.
Move the pointer a11y into ClutterSettings, making this effectively
backend-independent business, invariably done from the main thread
and ensured to happen after seat initialization.
Fixes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1765
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1849>
We've inherited, and still keep in place, code that reads ini files
at ~/.config/clutter-1.0/settings.ini and /etc/clutter-1.0/settings.ini
to tweak different aspects of Clutter.
Some of these should use GSettings instead, some others are exposed
nowadays differently for our purposes (e.g. envvars, looking glass, ...).
Overall seems like an unexpected entry point nowadays, so remove the
parsing of these .ini files altogether.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1693>
