/**
  * Adds/Edit a popup exception
  *
  * @param pattern attribute for the popup exception pattern
  * @param allow attribute to specify whether to allow or block pattern
  */
 public void setPopupException(String pattern, boolean allow) {
   nativeSetPopupException(
       pattern, allow ? ContentSetting.ALLOW.toInt() : ContentSetting.BLOCK.toInt());
 }