return false;
  }

  /** GWT emulated version of {@link ImmutableCollection.Builder}. */
  public abstract static class Builder<E> {

    Builder() {}

    static int expandedCapacity(int oldCapacity, int minCapacity) {
      if (minCapacity < 0) {
        throw new AssertionError("cannot store more than MAX_VALUE elements");
      }
      // careful of overflow!