[task scheduler] Fix scheduling on dead bots
[task scheduler] Fix scheduling on dead bots

Facepalm

BUG=skia:

Change-Id: I141c3f992f18f0aadb061945ecf6be4f504e29eb
Reviewed-on: https://skia-review.googlesource.com/5393
Commit-Queue: Eric Boren <0e499112533c8544f0505ea0d08394fb5ad7d8fa@google.com>
Reviewed-by: Eric Boren <0e499112533c8544f0505ea0d08394fb5ad7d8fa@google.com>

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