[cairo] [PATCH cairo] Drop the experimental skia backend

[Bryce Harrington]

On Sat, Sep 02, 2017 at 07:52:12PM +0930, Adrian Johnson wrote:
> On 22/08/17 07:17, Bryce Harrington wrote:
> > As has been stated in the README, skia is not API stable and is not
> > available packaged, versioned forms, resulting in it being a continually
> > moving target.  So the cairo skia backend has to be updated continually
> > as the skia API morphs, which means in practice that Cairo's skia
> > backend will always work only with a specific snapshot and lacking a
> > high degree of maintenance activity will always be badly out of date.
> > The last time the cairo skia backend was updated was in 2014, and had
> > not been updated very regularly prior to that.
> 
> Could we just comment it out in configure.ac to avoid presenting it as
> an option to users?

Of course, no reason that couldn't be done.  It'll just continue to
bitrot though.

How about this as a compromise, though?  We comment it out in trunk for
now, and see if anyone complains or if anyone voices an interest in skia
analysis work.  If none pops up by, say, the time we cut the next devel
snapshot, we apply this patch to remove the code for that snapshot.

The backend is relatively self-contained so if we did drop it and
someone needed it, then it wouldn't be that challenging for them to
resurrect it.  I suspect most of the effort would be in bringing it up
to date with skia, than with cairo; skia development moves far more
aggressively than cairo these days.

I'll note that the code doesn't cause any problems by it's presence, as
ickle rightly mentioned, but as it's dead code the purpose of removing
it is mainly in the interest of decluttering the codebase.

Bryce