The hidden-tab and teardown specs assumed the one scan addition after a
page closed its change stream is the write that finds the stream closed.
The server notices a closed stream only when a write fails, and nothing
orders the browser's close before that write: on WebKit under load the
close arrived after the change was written, the write succeeded, and the
stream stayed counted until the 25 s keepalive (CI job 120735035017).
Both specs now send no-op change notices (new fixture route
POST /__test__/review/notify) until the server has dropped the stream. A
new spec makes the CI ordering certain by holding the page's close until
the change has reached it.
Vito
e34bd70e13