make sure freed listeners are removed from list
remember export-dmabuf for when it's fixed in wlr
add output manager protocol
add screencopy support
While we're taking low-hanging fruit here...
add primary selection support too!
handle request set selection
Ported from wlroots commit fa5d709
use wlr_xdg_surface.set_tiled correctly
Closes #2. I'm guessing from sway that the idea of setting maximized
state so that windows cooperate is superseded by using set_tiled.
initialize global listeners statically
remove vestigial listeners
no need for a line split here
no conditional needed for output modes
If the output backend doesn't support modes, get_preferred_mode will
return NULL, and set_mode will accept NULL.
split xytoclient and xytosurface
raise client on refocus
Might revisit this later, but this currently seems like the right
strategy.