Mock notifier in test

app/scripts/controllers/preferences.js

@@ -35,6 +35,7 @@ class PreferencesController {
     }, opts.initState)
 
     this.getFirstTimeInfo = opts.getFirstTimeInfo || null
+    this.notifier = opts.notifier || notifier
 
     this.store = new ObservableStore(initState)
   }
@@ -129,7 +130,7 @@ class PreferencesController {
       // Notify our servers:
       const uri = 'https://diagnostics.metamask.io/v1/orphanedAccounts'
       const firstTimeInfo = this.getFirstTimeInfo ? this.getFirstTimeInfo() : {}
-      notifier.notify(uri, {
+      this.notifier.notify(uri, {
         accounts: Object.keys(newlyLost),
         metadata: {
           version,

test/unit/app/controllers/metamask-controller-test.js

@@ -72,6 +72,11 @@ describe('MetaMaskController', function () {
     it('removes any identities that do not correspond to known accounts.', async function () {
       const fakeAddress = '0xbad0'
       metamaskController.preferencesController.addAddresses([fakeAddress])
+      metamaskController.preferencesController.notifier = {
+        notify: async () => {
+          return true
+        },
+      }
       await metamaskController.submitPassword(password)
 
       const identities = Object.keys(metamaskController.preferencesController.store.getState().identities)