fails to build with newer cups.

[plugwash]

While working on raspbian I ran into a build failure of google-cloud-print-connector. It seems that cups no longer allows direct access to a number of data structures, forcing applications to use accesor methods instead.

I have whipped up a patch and it seems to build, but I have not tested it beyond that as I do not use google cloud printing. In particular I note that it seems the only way to iterate through the attributes changes ipp->next. I don't know why the the API is designed this way or if this will cause any problems. I also notice that ippGetValueTag applies a mask before returning the tag, again I don't know if that will cause any problems. Also I don't know go, so my changes to the go code should probablly be checked by someone who actually knows the langauge.

I have uploaded my fix to raspbian, a debdiff should appear soon at https://debdiffs.raspbian.org/main/g/google-cloud-print-connector/