This factors out the `Prefs` object from UnifiedComplete.js into UrlbarPreferences.jsm and makes required changes so it's not tied to consts and other identifiers local to UnifiedComplete.js. It adds another new module, UrlbarUtils.jsm, for storing consts that both UrlbarPreferences and UnifiedComplete use.
In order to preserve blame as much as possible, I used `hg cp` to copy UnifiedComplete.js to UrlbarPreferences.jsm, and then I removed all the non-Prefs code before making other changes, so this patch looks bigger than it really is. (Maybe I wasn't actually so successful in preserving a lot of blame.)
Differential Revision: https://phabricator.services.mozilla.com/D5626
--HG--
rename : toolkit/components/places/UnifiedComplete.js => browser/components/urlbar/UrlbarPrefs.jsm
extra : moz-landing-system : lando
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