Update GenericToken specialToken method to obtain only comment tokens

pmd-javascript/src/main/ant/alljavacc.xml

@@ -59,7 +59,7 @@ public class Token implements GenericToken, java.io.Serializable]]></replacevalu
   }
 
   @Override
-  public GenericToken getPreviousSpecialGenericToken() {
+  public GenericToken getPreviousComment() {
     return specialToken;
   }