gsd-color provides this API, which exposes details about the night light
state. Currently, gsd-color also turns this state into CRTC gamma
changes, but this will eventually change, and this is a preparation for
this.
The proxy isn't yet used for anything.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2164>
Previously, gsd-color handled adding color devices. It got information
about those via the GnomeRR API, which is part of libgnome-desktop.
libgnome-desktop itself got this information from the
org.gnome.Mutter.DisplayConfig.GetResources() D-Bus method, implemented
by mutter.
Now, mutter itself will add all the monitor color devices itself,
without having to go via gsd-color.
We sometimes need to delete colord devices synchronously, in certain
race conditions when we add and remove devices very quickly (e.g. in
tests). However, we cannot use libcolord's 'sync' API variants, as it
has a nested takes-all main loop as a way to invoke the sync call. This
effectively means we end up sometimes not return from this function in a
timely manner, causing wierd issues.
Instead, create our own sync helper, that uses a separate context that
we temporarly push as the thread-default one.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2141>
Create a color manager type that eventually will be the high level
manager of color related behavior, such as ICC profiles and
color "temperature" a.k.a. night light.
For now, it's only an empty shell. It's also constructed by the actual
backend, as at a later point, the X11 and native color management
implementations will differ.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2141>
