Don't block API requests on the auth dialog

The auth dialog waits for the background authentication check to fail,
but it shouldn't replace that promise with its own. It is perfectly
fine for the application to proceed while the user is entering
credentials.

In particular, this makes sure that a search without any authorization
can be performed even when the firstrun flag causes the login dialog
to show.

h/static/scripts/config/identity.js

@@ -113,7 +113,6 @@ function forgetAuthentication($q, flash, session) {
 function requestAuthentication($injector, $q, $rootScope) {
   return authPromise.catch(function () {
     var deferred = $q.defer();
-    authPromise = deferred.promise;
 
     $rootScope.$on('auth', function(event, err, data) {
       if (err) {
@@ -125,7 +124,7 @@ function requestAuthentication($injector, $q, $rootScope) {
       }
     });
 
-    return authPromise;
+    return deferred.promise;
   });
 }