Merge "Fix NPE when removing policies." into udc-dev

     * Removes all local policies for the provided {@code userId}.

     */

    private void removeLocalPoliciesForUser(int userId) {

        if (!mLocalPolicies.contains(userId)) {

            // No policies on user

            return;

        }

        Set<PolicyKey> localPolicies = new HashSet<>(mLocalPolicies.get(userId).keySet());

        for (PolicyKey policy : localPolicies) {

            PolicyState<?> policyState = mLocalPolicies.get(userId).get(policy);