Bug 1167601 - Follow-up to fix an a11y test that assumed that about:newtab was still XUL. r=tbsaunde

--HG--
extra : commitid : 8JZGnT8g5FR

accessible/tests/mochitest/tree/test_tabbrowser.xul

@@ -180,7 +180,7 @@
                   children: [
                     {
                       // #document ("about:newtab" preloaded)
-                      role: ROLE_APPLICATION
+                      role: ROLE_DOCUMENT
                       // children: [ ... ] // Ignore document content.
                     }
                   ]