Using out-of-band notifications from the wayland protocol or from
X is racy, in that the client could ask for the new resources before
we have them.
Instead, with a signal, we are sure that when the client asks for
it, it will get the right values.
https://bugzilla.gnome.org/show_bug.cgi?id=706382
Add GetCrtcGamma() and SetCrtcGamma(), that wrap the similarly
named XRandR API. These are used by GnomeRR inside the color
plugin of the control center (and may go away if the color
plugin decides to do something different under wayland)
https://bugzilla.gnome.org/show_bug.cgi?id=705670
GnomeRR needs that too.
The backlight is exported as a normalized 0-100 value, or -1 if not
supported. Clamping to HW limits is handled by the backend.
Changing backlight uses a different method call, to avoid recomputing
the full display configuration every time the user presses the
backlight keys.
https://bugzilla.gnome.org/show_bug.cgi?id=705670
Implement ApplyConfiguration in terms of XRandR calls.
Error checking is done before actually committing the configuration.
If mutter is using one of the other monitor config backends, an
error is reported and nothing happens.
https://bugzilla.gnome.org/show_bug.cgi?id=705670
Turns out that even if two outputs say that they can be controlled
by a given CRTC, you can't configure them in the same CRTC unless
they are marked as "possible clones" one of the other.
This can further restrict the configuration options, so we need
to expose this limitation in the DBus API.
https://bugzilla.gnome.org/show_bug.cgi?id=705670
This new interface will be used by the control center and possibly
the settings daemon to configure the screens. It is designed to
resemble a simplified XRandR, while still exposing all the quirks
of the hardware, so that the panel can limit the user choices
appropriately.
To do so, MetaMonitorMode needs to track CRTCs, outputs and modes,
so the low level objects have been decoupled from the high-level
MetaMonitorInfo, which is used by core and API and offers a simplified
view of HW, that hides away the details of what is cloned and how.
This is still not efficient as it should be, because on every
HW change we drop all data structures and rebuild them from scratch
(which is not expensive because there aren't many of them, but
at least in the XRandR path it involves a few sync X calls)
https://bugzilla.gnome.org/show_bug.cgi?id=705670
