Warn about missing binary/bazel build instead of dirname errors (#683)
Warn about missing binary/bazel build instead of dirname errors (#683)

Fixes issue #676
douglas-reid/mixer,rkpagadala/mixer,rkpagadala/mixer,douglas-reid/mixer,xiaolanz/mixer,xiaolanz/mixer,guptasu/mixer,ZackButcher/mixer,istio/old_mixer_repo,guptasu/mixer,jmuk/mixer,ZackButcher/mixer,xiaolanz/mixer,istio/old_mixer_repo,istio/old_mixer_repo,guptasu/mixer,rkpagadala/mixer,douglas-reid/mixer,jmuk/mixer,ZackButcher/mixer,jmuk/mixer