gold: Status should only have at most one request in flight at any one time.
gold: Status should only have at most one request in flight at any one time.

BUG=skia:
TBR=stephana

Review URL: https://codereview.chromium.org/1148823004

Tiger66639/skia-buildbot,Tiger66639/skia-buildbot,google/skia-buildbot,Tiger66639/skia-buildbot,google/skia-buildbot,google/skia-buildbot,Tiger66639/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,Tiger66639/skia-buildbot,Tiger66639/skia-buildbot,Tiger66639/skia-buildbot,google/skia-buildbot