Revert of Add logging to prober to help identify cause of hang. (patchset #1 id:1 of https://codereview.chromium.org/2105453002/ )
Revert of Add logging to prober to help identify cause of hang. (patchset #1 id:1 of https://codereview.chromium.org/2105453002/ )

Reason for revert:
I haven't seen a hang since https://codereview.chromium.org/2103703005

Original issue's description:
> Add logging to prober to help identify cause of hang.
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/buildbot/+/3fdc834e7ce854d2637b13761a22213ebaf08d8b

# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=skia:5468

Review-Url: https://codereview.chromium.org/2121393002

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