Some x86 clamshell design devices use portrait tablet LCD panels while
they should use a landscape panel, resoluting in a 90 degree rotated
picture.
Newer kernels detect this and rotate the fb console in software to
compensate. These kernels also export their knowledge of the LCD panel
orientation vs the casing in a "panel orientation" drm_connector property.
This commit adds support to mutter for reading the "panel orientation"
and transparently (from a mutter consumer's pov) fixing this by applying
a (hidden) rotation transform to compensate for the panel orientation.
Related: https://bugs.freedesktop.org/show_bug.cgi?id=94894https://bugzilla.gnome.org/show_bug.cgi?id=782294
In order to eventually support multilpe GPUs with their own connectors,
split out related meta data management (i.e. outputs, CRTCs and CRTC
modes) into a new MetaGpu GObject.
The Xrandr backend always assumes there is always only a single "GPU" as
the GPU is abstracted by the X server; only the native backend (aside
from the test backend) will eventually see more than one GPU.
The Xrandr backend still moves some management to MetaGpuXrandr, in
order to behave more similarly to the KMS counterparts.
https://bugzilla.gnome.org/show_bug.cgi?id=785381
Instead of passing it around or fetching the singleton, keep a pointer
to the monitor manager that owns the output. This will eventually be
replaced with a per GPU/graphics card object.
https://bugzilla.gnome.org/show_bug.cgi?id=785381
Turn MetaOutput into a GObject and move it to a separate file. This
changes the storage format, resulting in changing the API for accessing
MetaOutputs from using an array, to using a GList.
https://bugzilla.gnome.org/show_bug.cgi?id=785381
