This was almost certainly my fault, but as I look at the implementation of Sets.cartesianProduct, I think its `contains` method made the assumption that `ImmutableSet.asList().indexOf` was O(1), which is no longer the case for Android.  It should probably get a specific `contains` implementation that actually is O(sets), not O(sets*setSize).
*
     * @return a reference to {@code set}, for convenience
     */
    
    
    @CanIgnoreReturnValue
    public <S extends Set<E>> S copyInto(S set) {
      set.addAll(this);
      return set;
    }
    /**
     * Guaranteed to throw an exception and leave the collection unmodified.
     *
     * @throws UnsupportedOperationException always
     * @deprecated Unsupported operation.
     */
    @CanIgnoreReturnValue
    @Deprecated
    @Override
    public final boolean add(E e) {
      throw new UnsupportedOperationException();
    }
    /**
     * Guaranteed to throw an exception and leave the collection unmodified.
     *
     * @throws UnsupportedOperationException always
     * @deprecated Unsupported operation.
     */
    @CanIgnoreReturnValue
    @Deprecated