fix(firestore): call useEmulator after enablePersistence to fix "already started" issue

Call useEmulator after enablePersistence to fix "Firestore has already been started" issue

re #451

Author: lupas

lib/plugins/services/firestore.js

@@ -11,6 +11,19 @@ export default async function (session) {
     firestoreService.settings(<%= serialize(serviceOptions.settings) %>)
   <% } %>
 
+  <% /* Uses emulator, if emulatorPort is set. */ %>
+  <% if (['string', 'number'].includes(typeof serviceOptions.emulatorPort)) { %>
+  <% const emulatorHost =
+  typeof serviceOptions.emulatorHost === 'string'
+    ? serviceOptions.emulatorHost
+    : 'localhost'
+  %>
+  // If statement fixes Issue #390, only runs useEmulator when not yet called (relevant on server) 
+  if (process.client || firestoreService._delegate._settings.host === 'firestore.googleapis.com') {
+    firestoreService.useEmulator('<%= `${emulatorHost}` %>', <%= `${serviceOptions.emulatorPort}` %>)
+  }
+  <% } %>
+
   <% if (serviceOptions.enablePersistence) { %>
   // persistence should only be enabled client side
   if (process.client) {
@@ -27,18 +40,5 @@ export default async function (session) {
   }
   <% } %>
 
-  <% /* Uses emulator, if emulatorPort is set. */ %>
-  <% if (['string', 'number'].includes(typeof serviceOptions.emulatorPort)) { %>
-  <% const emulatorHost =
-  typeof serviceOptions.emulatorHost === 'string'
-    ? serviceOptions.emulatorHost
-    : 'localhost'
-  %>
-  // If statement fixes Issue #390, only runs useEmulator when not yet called (relevant on server) 
-  if (process.client || firestoreService._delegate._settings.host === 'firestore.googleapis.com') {
-    firestoreService.useEmulator('<%= `${emulatorHost}` %>', <%= `${serviceOptions.emulatorPort}` %>)
-  }
-  <% } %>
-
   return firestoreService
 }