Merge "Don't show tipsy for an unknown language"

lib/jquery.uls/src/jquery.uls.data.utils.js

@@ -42,6 +42,11 @@
 			return $.uls.data.getScript( target );
 		}
 
+		if ( !$.uls.data.languages[language] ) {
+			// Undetermined
+			return 'Zyyy';
+		}
+
 		return $.uls.data.languages[language][0];
 	};
 

resources/js/ext.uls.interface.js

@@ -179,7 +179,7 @@
 			return true;
 		}
 
-		if ( previousLang === currentLang ) {
+		if ( previousLang === currentLang || !$.uls.data.languages[previousLang] ) {
 			// Do not show tooltip.
 			return true;
 		}