New history refresh prevents push/tab notification of job completions

[astrovsky01]

Describe the bug A clear and concise description of what the bug is.

Tab and push notifications for job completion no longer function with the new history. When enabled by users, the notifications create a count or a red galaxy logo on the tab bar, as well as a push notification whenever a job completes and a user is not focused on the Galaxy tab. With the new history, the history does not update until it is in focus, meaning the notifications will never be sent

Galaxy Version and/or server at which you observed the bug US, EU

To Reproduce Steps to reproduce the behavior:

1. Turn on job notifications from the User preferences
2. Run job
3. Exit to new tab before job completes
4. Wait for job to complete

Expected behavior Tab should either update to show "Galaxy (x)" with "x" being the number of jobs completed, or the galaxy logo should turn red to demonstrate an error, and a push notification should be sent for job completion either way

Additional context Discussion needed for how to fix, because the refresh only on focus was intended to decrease server load

[mvdbeek]

Yes, we stop polling the history for changes when the tab isn't active. It's very expensive to poll for history datasets (we have never actually polled for jobs) when the tab isn't active. We should probably remove the notification, it only seems marginally useful. Alternatively we can throttle the requests aggressively.

[dannon]

Two things:

• Instead of stopping, dramatically back off polling when in background. 1-2m or so, instead of stopped.
• Add client preference configurability for notifications

[martenson]

Potentially also consider unification with #15663