[Build] Fix GenericSearchProvider spec

...by delegating  to window.setTimeout, such
that spec as-written behaves correctly.

platform/search/test/services/GenericSearchProviderSpec.js

@@ -81,6 +81,10 @@ define([
 
             spyOn(GenericSearchProvider.prototype, 'scheduleForIndexing');
 
+            $timeout.andCallFake(function (callback, millis) {
+                window.setTimeout(callback, millis);
+            });
+
             provider = new GenericSearchProvider(
                 $timeout,
                 $q,