vaapisink: wayland: add support for wl_viewporter extension
Submitted by Gwenole Beauchesne @gb
Link to original bug (#736734)
Description
The wl_scaler extension is to be useful for presenting VA surfaces with additional scaling, and possibly cropping information, thus avoiding an ad-hoc VPP pipeline.
It should be worth trying this out. Though, we would still be missing basic support for bob-deinterlacing.