`UnmodifiableMultimap.forEach` uses the `Multimap.forEach` default implementation which involves listing entries, and creating a new lambda instead of simply passing the BiConsumer through to the protected instance. This is safe to pass directly though because `forEach(BiConsumer)` is a read-only operation.
@Override
    public void clear() {
      fromMultimap.clear();
    }
    @Override
    public boolean containsKey(Object key) {
      return fromMultimap.containsKey(key);
    }
    @Override
    Collection<Entry<K, V2>> createEntries() {
      return new Entries();
    }
    @Override
    Iterator<Entry<K, V2>> entryIterator() {
      return Iterators.transform(
          fromMultimap.entries().iterator(), Maps.<K, V1, V2>asEntryToEntryFunction(transformer));
    }
    @Override
    public Collection<V2> get(final K key) {
      return transform(key, fromMultimap.get(key));
    }
    @Override
    public boolean isEmpty() {
      return fromMultimap.isEmpty();
    }
    @Override
    Set<K> createKeySet() {
      return fromMultimap.keySet();
    }
    @Override