Normally autocomplete results are cached based upon the search string but to get the desired behaviour we want two different sets of results for the same search string depending on how the autocomplete search was started:
a) Via automatically focusing a password field.
b) Every other method of starting an autocomplete search.
In order to not have cached results used, the result code for case (a) [an empty result] will be `RESULT_FAILURE` and I've updated the autocomplete code to not re-use an error result.
In the coming months we may be rewriting our content autocomplete code but that would be too risky to uplift to 67 so for now I'm tracking when satchel automatically opens the popup upon focus and then using that state in the autocomplete result creation code to know whether to include the footer.
Differential Revision: https://phabricator.services.mozilla.com/D25173
e24ba068b6