xkbfile dependency

[grue-bleen]

on ubuntu 20.10:

Package xkbfile was not found in the pkg-config search path.
Perhaps you should add the directory containing xkbfile.pc' to the PKG_CONFIG_PATH environment variable No package 'xkbfile' found gyp: Call to '${PKG_CONFIG:-pkg-config} x11 xkbfile --cflags | sed s/-I//g' returned exit status 0 while in binding.gyp. while trying to load binding.gyp gyp ERR! configure error gyp ERR! stack Error: gyp` failed with exit code: 1

installing libxkbfile-dev fixed it.

[vince-fugnitto]

@cyrilchemparathy are you suggesting updating our prerequisites?
If you don't mind, would you like to contribute the changes (it's currently referenced for debian)?

[grue-bleen]

certainly, happy to update prerequisites. .travis.yml has the dependency, and a few more (libsecret-1-dev, xvfb, ...). presumably should include all in prerequisites.