Revert of Domain Reliability: Switch to BackoffEntry in Scheduler (patchset #4 id:60001 of https://codereview.chromium.org/
704893002/)
Reason for revert:
Speculative revert to attempt to fix https://code.google.com/p/chromium/issues/detail?id=431608
Original issue's description:
> Domain Reliability: Switch to BackoffEntry in Scheduler
>
> Previously, Domain Reliability was using homegrown backoff handling code.
> Switch to using the existing BackoffEntry.
>
> BUG=
>
> Committed: https://crrev.com/
dd6819b1522473ae11b98cb60b8b613af01f4b56
> Cr-Commit-Position: refs/heads/master@{#303296}
TBR=davidben@chromium.org,ttuttle@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=
Review URL: https://codereview.chromium.org/
709333003
Cr-Commit-Position: refs/heads/master@{#303412}