Two mozconfg additions are necessary for these jobs on linux:
1.) Turning off the clang plugin, which will not get built during these builds
and will cause failures when C/C++ needed by the rust build tries to find it.
2.) Adding --output-sync=line to our make invocation: at some point the
"export" phase started relying on this, and it's missing because the
non-default build targets invoked by the rusttests builds don't go through
client.mk.
Differential Revision: https://phabricator.services.mozilla.com/D11242
--HG--
extra : moz-landing-system : lando
We need mozharness configurations and mozconfigs for rusttests. We are
explicitly not doing Windows debug configurations currently because of
peculiar link errors in such configurations.