Merge cherrypicks of [16905018] into security-aosp-rvc-release.

    public static final String FILE_NAME = "phone-account-registrar-state.xml";

    @VisibleForTesting

    public static final int EXPECTED_STATE_VERSION = 9;

    public static final int MAX_PHONE_ACCOUNT_REGISTRATIONS = 10;

    /** Keep in sync with the same in SipSettings.java */

    private static final String SIP_SHARED_PREFERENCES = "SIP_PREFERENCES";

        return account.isSelfManaged();

    }

    // TODO: Should we implement an artificial limit for # of accounts associated with a single

    // ComponentName?

    /**

     * Performs checks before calling addOrReplacePhoneAccount(PhoneAccount)

     *

     * @param account The {@code PhoneAccount} to add or replace.

     * @throws SecurityException if package does not have BIND_TELECOM_CONNECTION_SERVICE permission

     * @throws IllegalArgumentException if MAX_PHONE_ACCOUNT_REGISTRATIONS are reached

     */

    public void registerPhoneAccount(PhoneAccount account) {

        // Enforce the requirement that a connection service for a phone account has the correct

        // permission.

            throw new SecurityException("PhoneAccount connection service requires "

                    + "BIND_TELECOM_CONNECTION_SERVICE permission.");

        }

        //Enforce an upper bound on the number of PhoneAccount's a package can register.

        // Most apps should only require 1-2.

        if (getPhoneAccountsForPackage(

                account.getAccountHandle().getComponentName().getPackageName(),

                account.getAccountHandle().getUserHandle()).size()

                >= MAX_PHONE_ACCOUNT_REGISTRATIONS) {

            Log.w(this, "Phone account %s reached max registration limit for package",

                    account.getAccountHandle());

            throw new IllegalArgumentException(

                    "Error, cannot register phone account " + account.getAccountHandle()

                            + " because the limit, " + MAX_PHONE_ACCOUNT_REGISTRATIONS

                            + ", has been reached");

        }

        addOrReplacePhoneAccount(account);

    }