When we make a change to a timer, we have to note the
desired change to t.when and then wait for the timer heap
owner to apply the change. There are two possible changes:
delete or set a new t.when. Most of the code for processing
these changes is the same, so we can simplify the code by
making both have the same state: timerDeleted is now
timerModified with t.nextwhen == 0.
This is part of a larger simplification of the state set.
[This is one CL in a refactoring stack making very small changes
in each step, so that any subtle bugs that we miss can be more
easily pinpointed to a small change.]
Change-Id: I1a2a12f8250bcd40f7b08b83f22c3a82b124eda6
Reviewed-on: https://go-review.googlesource.com/c/go/+/564123 Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>