Let's rather not build the plugin if we don't have the dependency
then building it without OpenGL support. Simplifies the code a bit
and makes the backend overall more useful and goes along with e.g.
the Wayland one which has EGL also as a hard dependency for the
plugin.
REVIEW: 124697
It doesn't make much sense any more as we do no longer link EGL since the
switch to epoxy. And epoxy pulls it in at runtime if needed.
Even more on Wayland it's just plain stupid to have EGL disabled. So
removing the option just simplifies our code base without any
disadvantages.
REVIEW: 124695
We don't need to queue the method invokation any more to ensure the
Wayland server connection is flushed since we have the dispatch method
in waylandServer().
Each of the backends becomes a plugin. This allows kwin_wayland to load
the requested plugin and kwin itself doesn't need to link all the
libraries needed. E.g. libdrm is no longer linked if running kwin_x11.
Also this allows to create backends for the non-standard EGL platforms
(examples could be raspberrypi or Android devices).
With this change all backends need to emit the screensQueried signal
at some point. So far only x11 backend did not provide the signal,
wayland had a comparable delayed init mechanism. Now all backends use
the same mechanism.
Replaces the functionality of the WaylandBackend and makes it available
to all backends by providing the functionality directly in
AbstractBackend. By default a backend is not ready and the implementation
must call setReady(true) to indicate that setup has finished
successfully. The compositor won't start till the backend indicates that
it is ready.
The aim is to be able to create a plugin for each of the backends.
The following directories are created:
* backends/drm
* backends/fbdev
* backends/wayland
* backends/x11
