Sometimes reviews are posted to a change while it's in the WIP state.
The owner may be preparing guidance for their upcoming reviewers, or a
CI bot may be reporting about tests. In general, for the purpose of
filtering messages, we distinguish between bot and human actions on the
basis of whether a tag is provided. A non-null tag is assumed to
indicate automation.
For reviews posted by humans, the default notify level depends on
whether hasReviewStarted is true for the change. If a new WIP change is
created and pending reviewers are added, those reviewers should never
receive an email about the change until the owner starts review.
Therefore, when WIP is true, hasReviewStarted is false, and tag is
null, the default notify level is downgraded from ALL to OWNER. If the
change has started review, the default notify level continues to be ALL
(only if tag is null).
For reviews posted by bots, the default notify level is downgraded for
all WIP changes, even after they've entered review. For example, a CI
bot may post failing test results for a series of intermediate patch
sets. This is just noise to reviewers, but useful to the owner, so when
WIP is true and tag is non-null, the default notify level is downgraded
to OWNER.
Change-Id: I93395e36470090377d2120bb8136e7c11670d224
ea3e3b704a