@Override
        public boolean containsAll(Collection<?> collection) {
            Iterator<?> it = collection.iterator();
            while (it.hasNext()) {
                if (!contains(it.next())) {
                    return false;
                }
            }
            return true;
        }
Helper for writing standard Java collection interfaces to a data
structure like {@link ArrayMap}.
android/android_framework/base/src/main/java/github/tornaco/android/thanos/core/util/collection/MapCollections.java