Adaptive history and enable add search engine button

Adaptive history sorts URL bar results better,
and enables add search engine button in the
search settings.

src/user.js

@@ -55,6 +55,7 @@ user_pref('browser.startup.homepage_override.mstone', 'ignore');
 user_pref('browser.tabs.hoverPreview.showThumbnails', false);
 user_pref('browser.tabs.warnOnClose', false);
 user_pref('browser.uitour.enabled', false);
+user_pref('browser.urlbar.autoFill.adaptiveHistory.enabled', true);
 user_pref('browser.urlbar.clickSelectsAll', true);
 user_pref('browser.urlbar.doubleClickSelectsAll', false);
 user_pref('browser.urlbar.matchBuckets', 'general:5,suggestion:Infinity');
@@ -72,6 +73,7 @@ user_pref('browser.urlbar.suggest.quicksuggest.sponsored', false);
 user_pref('browser.urlbar.suggest.recentsearches', false);
 user_pref('browser.urlbar.suggest.searches', false);
 user_pref('browser.urlbar.timesBeforeHidingSuggestionsHint', 0);
+user_pref('browser.urlbar.update2.engineAliasRefresh', true);
 user_pref('datareporting.healthreport.uploadEnabled', false);
 user_pref('datareporting.policy.dataSubmissionEnabled', false);
 user_pref('devtools.inspector.show-three-pane-tooltip', false);