fix(subscriptions): respond with empty subscription list fo r 403 error from subhub

packages/fxa-auth-server/lib/subhub/client.js

@@ -190,6 +190,9 @@ module.exports = function(log, config) {
           log.error('subhub.listSubscriptions.1', { uid, err });
           throw error.unknownCustomer(uid);
         }
+        if (err.statusCode === 403) {
+          return { subscriptions: [] };
+        }
         throw err;
       }
     },

packages/fxa-auth-server/test/local/subhub/client.js

@@ -151,6 +151,15 @@ describe('subhub client', () => {
       assert.deepEqual(resp, expected);
     });
 
+    it('should yield an empty list for 403 no subscriptions error', async () => {
+      mockServer
+        .get(`/v1/customer/${UID}/subscriptions`)
+        .reply(403, { message: 'No subscriptions for this customer.' });
+      const { subhub } = makeSubject();
+      const resp = await subhub.listSubscriptions(UID);
+      assert.deepEqual(resp, { subscriptions: [] });
+    });
+
     it('should throw on unknown user', async () => {
       mockServer
         .get(`/v1/customer/${UID}/subscriptions`)