This checks for whether local storage is enabled and if it
is not enabled, then it will skip checking the value of
"dontAskForNotifications" key in the local storage.
This should eliminate an occasional JavaScript traceback we were
seeing in production.
Fixes#8721.
Also refactor the "panels"/banner code to be a bit clearer about how
it's supposed to generically work, using [data-process] as a uniquely
identifying marker.
Fixes: #8166.
[greg: rebased and squashed a series of fixup commits.]
The original code made a 3/4-hearted effort to generically accommodate
more banners/"panels" later, but named itself after the first one made.
[greg: expanded commit message.]
Aastha Gupta
Brock Whittaker