code: public boolean isSuperset(SmallSet<E> other) {
          if (this.list.size() < other.list.size()) {
              return false;
          }
          int j = 0;
          for (int i=0; i<list.size() && j<other.list.size(); i++) {
              E e1 = this.list.get(i);
              E e2 = other.list.get(j);
              int diff = e1.compareTo(e2);
              if (diff == 0) {
                  // Equal entries. Just continue.
                  j++;
                  continue;
              } else if (diff > 0) {
                  // e1 is greater than e2, which means e2 must not appear in this.list.
                  return false;
              } else {
                  // e1 is less than e2, so e2 might appear later in this.list.
                  continue;
              }
          }
          if (j == other.list.size()) {
              return true;
          } else {
              return false;
          }
      }
docs: TODO: containsAll should call this and it should become private.