static <A, B> void removeFromMapWhereValue(Map<A, B> map, IPred<B> pred) {
  if (map == null) ret;
  Iterator<Map.Entry<A, B>> i = map.entrySet().iterator();
  while (i.hasNext()) {
    Map.Entry<A, B> e = i.next();
    if (pred.get(e.getValue()))
      i.remove();
  }
}

Began life as a copy of #1027983