This is so that we can avoid needing mozSystemGroup (to get keypress for
non-printable keys), which in turn prevents racing with the native key event
listeners, see the second patch in bug 1624657.
This turned out to be a bit tricky, because we need to guarantee the ordering of
the search one-offs handling in the searchbar with the usual autocomplete-input
handling. We could try to move this to the popup subclass but this is already a
bigger patch than what I'd like.
We can also revert the customElements.js change I did in bug 1624657, as the bug
is no longer relevant.
Differential Revision: https://phabricator.services.mozilla.com/D69743
--HG--
extra : moz-landing-system : lando
d547edb535