Merge "Throw illegal state exception when service is not available"

     * @param callback Callback will be triggered once it succeeds or failed.

     *                 Pass null if don't care about the result.

     *

     * @throws IllegalStateException when subscription manager service is not available.

     * @throws SecurityException when clients do not have MODIFY_PHONE_STATE permission.

     * @hide

     *

     */

    @SystemApi

    @RequiresPermission(android.Manifest.permission.MODIFY_PHONE_STATE)

        if (VDBG) logd("[setPreferredDataSubscriptionId]+ subId:" + subId);

        try {

            ISub iSub = TelephonyManager.getSubscriptionService();

            if (iSub == null) return;

            if (iSub == null) {

                throw new IllegalStateException("subscription manager service is null.");

            }

            ISetOpportunisticDataCallback callbackStub = new ISetOpportunisticDataCallback.Stub() {

                @Override

            };

            iSub.setPreferredDataSubscriptionId(subId, needValidation, callbackStub);

        } catch (RemoteException ex) {

            // ignore it

            loge("setPreferredDataSubscriptionId RemoteException=" + ex);

            ex.rethrowFromSystemServer();

        }

    }