Fix slave_hosts_cfg
Fix slave_hosts_cfg

TBR=rmistry
BUG=skia:

Review URL: https://codereview.chromium.org/1610113002

google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot