code: static <T> boolean iterableContains(Iterable<T> iterable, T item) {
      if (iterable instanceof Collection) {
        Collection<?> collection = (Collection<?>) iterable;
        try {
          return collection.contains(item);
        } catch (NullPointerException e) {
          return false;
        } catch (ClassCastException e) {
          return false;
        }
      }
      for (T i : iterable) {
        if (Objects.equal(i, item)) {
          return true;
        }
      }
      return false;
    }
docs: Checks whether the given item exists in the iterable.  This is copied from Guava Collect's
  {@code Iterables.contains()} because Guava Collect is not Android-friendly thus core can't
  depend on it.