code: @ReplacedBy("com.google.common.collect.Iterators#addAll()")
      public static <T, C extends Collection<T>> C addAll (C col, Iterator<? extends T> iter)
      {
          while (iter.hasNext()) {
              col.add(iter.next());
          }
          return col;
      }
docs: Adds all items returned by the iterator to the supplied collection and
  returns the supplied collection.