Move the KMS interaction from cogl into mutter, where most of the other
KMS interaction already takes place. This also removes dead code which
were only excercised when non-mutter callers used the cogl KMS backend.
The cogl KMS API was updated to pass via MetaRendererNative instead of
via the different cogl objects.
https://bugzilla.gnome.org/show_bug.cgi?id=768976
Instead of passing around the KMS file descriptor via clutter to cogl,
just make our own clutter backend create the cogl renderer and set the
KSM fd.
https://bugzilla.gnome.org/show_bug.cgi?id=768976
MetaRenderer is meant to be the object responsible for rendering the
scene graph. It will contain the logic related to the cogl winsys
backend, the clutter backend, and the clutter stage window.
https://bugzilla.gnome.org/show_bug.cgi?id=768976
