Allow Android account manager to refresh the access token

app/src/main/java/eu/faircode/email/ServiceSynchronize.java

@@ -21,6 +21,8 @@ package eu.faircode.email;
 
 import static android.os.Process.THREAD_PRIORITY_BACKGROUND;
 
+import static eu.faircode.email.ServiceAuthenticator.AUTH_TYPE_PASSWORD;
+
 import android.app.AlarmManager;
 import android.app.NotificationManager;
 import android.app.PendingIntent;
@@ -1421,6 +1423,12 @@ public class ServiceSynchronize extends ServiceBase implements SharedPreferences
                                     Log.e(ex);
                             } else {
                                 Log.e(ex);
+
+                                // Allow Android account manager to refresh the access token
+                                if (account.auth_type != AUTH_TYPE_PASSWORD &&
+                                        state.getBackoff() <= CONNECT_BACKOFF_INTERMEDIATE * 60)
+                                    throw ex;
+
                                 try {
                                     state.setBackoff(2 * CONNECT_BACKOFF_ALARM_MAX * 60);
                                     NotificationManager nm = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);