Do not propagate enter event to parent page elements from ULS search box

Change-Id: I18b8b746ed8bff2b0e06a8b05a2c6e69c7899293

src/jquery.uls.languagefilter.js

@@ -82,6 +82,10 @@
 						break;
 					}
 
+					// Avoid bubbling this 'enter' to background page elements
+					e.preventDefault();
+					e.stopPropagation();
+
 					query = $.trim( this.$element.val() ).toLowerCase();
 
 					if ( this.selectedLanguage ) {