Bug 1548141 - Ensure SearchService has started. r=mikedeboer

Differential Revision: https://phabricator.services.mozilla.com/D29430

--HG--
extra : moz-landing-system : lando

browser/components/urlbar/UrlbarUtils.jsm

@@ -167,6 +167,7 @@ var UrlbarUtils = {
       return { url, postData, mayInheritPrincipal };
     }
 
+    await Services.search.init();
     let engine = Services.search.getEngineByAlias(keyword);
     if (engine) {
       let submission = engine.getSubmission(param, null, "keyword");