Program: 33702
Project: 33702
Buggy source:
@Override protected Result doInBackground(String... params){
  String modelKey=settings.modelKey;
  ArrayList<String> notifications=settings.enabledNotifications;
  boolean isFavorite=settings.isFavorite;
  String user=AccountHelper.getSelectedAccount(context);
  String key=MyTBAHelper.createKey(user,modelKey);
  ModelsMobileApiMessagesModelPreferenceMessage request=new ModelsMobileApiMessagesModelPreferenceMessage();
  request.setModelKey(modelKey);
  request.setDeviceKey(GCMAuthHelper.getRegistrationId(context));
  request.setNotifications(notifications);
  request.setFavorite(isFavorite);
  Database.Subscriptions subscriptionsTable=Database.getInstance(context).getSubscriptionsTable();
  Database.Favorites favoritesTable=Database.getInstance(context).getFavoritesTable();
  List<String> existingNotificationsList=new ArrayList<>();
  Subscription existingSubscription=subscriptionsTable.get(key);
  if (existingSubscription != null) {
    existingNotificationsList=existingSubscription.getNotificationList();
  }
  Collections.sort(notifications);
  Collections.sort(existingNotificationsList);
  boolean notificationsHaveChanged=!(notifications.equals(existingNotificationsList));
  if (((isFavorite && favoritesTable.exists(key)) || (!isFavorite && !favoritesTable.exists(key))) && notificationsHaveChanged) {
    return Result.NOOP;
  }
 else {
    try {
      TbaMobile service=AccountHelper.getAuthedTbaMobile(context);
      ModelsMobileApiMessagesBaseResponse response=service.model().setPreferences(request).execute();
      JsonObject responseJson=JSONManager.getasJsonObject(response.getMessage());
      JsonObject fav=responseJson.get("String_Node_Str").getAsJsonObject(), sub=responseJson.get("String_Node_Str").getAsJsonObject();
      int favCode=fav.get("String_Node_Str").getAsInt(), subCode=sub.get("String_Node_Str").getAsInt();
      if (subCode == 200) {
        if (notifications.isEmpty()) {
          subscriptionsTable.remove(key);
        }
 else         if (subscriptionsTable.exists(key)) {
          subscriptionsTable.update(key,new Subscription(user,modelKey,notifications));
        }
 else {
          subscriptionsTable.add(new Subscription(user,modelKey,notifications));
        }
      }
 else       if (subCode == 500) {
        Toast.makeText(context,String.format(context.getString(R.string.mytba_error),subCode,sub.get("String_Node_Str").getAsString()),Toast.LENGTH_SHORT).show();
      }
      if (favCode == 200) {
        if (!isFavorite) {
          favoritesTable.remove(key);
        }
 else         if (favoritesTable.exists(key)) {
        }
 else {
          favoritesTable.add(new Favorite(user,modelKey));
        }
      }
 else       if (favCode == 500) {
        Toast.makeText(context,String.format(context.getString(R.string.mytba_error),favCode,fav.get("String_Node_Str").getAsString()),Toast.LENGTH_SHORT).show();
      }
      return Result.SUCCESS;
    }
 catch (    IOException e) {
      Log.e(Constants.LOG_TAG,"String_Node_Str");
      e.printStackTrace();
      return Result.ERROR;
    }
  }
}

Fixed version (ground truth):
@Override protected Result doInBackground(String... params){
  String modelKey=settings.modelKey;
  ArrayList<String> notifications=settings.enabledNotifications;
  boolean isFavorite=settings.isFavorite;
  String user=AccountHelper.getSelectedAccount(context);
  String key=MyTBAHelper.createKey(user,modelKey);
  ModelsMobileApiMessagesModelPreferenceMessage request=new ModelsMobileApiMessagesModelPreferenceMessage();
  request.setModelKey(modelKey);
  request.setDeviceKey(GCMAuthHelper.getRegistrationId(context));
  request.setNotifications(notifications);
  request.setFavorite(isFavorite);
  Database.Subscriptions subscriptionsTable=Database.getInstance(context).getSubscriptionsTable();
  Database.Favorites favoritesTable=Database.getInstance(context).getFavoritesTable();
  List<String> existingNotificationsList=new ArrayList<>();
  Subscription existingSubscription=subscriptionsTable.get(key);
  if (existingSubscription != null) {
    existingNotificationsList=existingSubscription.getNotificationList();
  }
  Collections.sort(notifications);
  Collections.sort(existingNotificationsList);
  Log.d(Constants.LOG_TAG,"String_Node_Str" + notifications.toString());
  Log.d(Constants.LOG_TAG,"String_Node_Str" + existingNotificationsList.toString());
  boolean notificationsHaveChanged=!(notifications.equals(existingNotificationsList));
  if (((isFavorite && favoritesTable.exists(key)) || (!isFavorite && !favoritesTable.exists(key))) && !notificationsHaveChanged) {
    return Result.NOOP;
  }
 else {
    try {
      TbaMobile service=AccountHelper.getAuthedTbaMobile(context);
      ModelsMobileApiMessagesBaseResponse response=service.model().setPreferences(request).execute();
      JsonObject responseJson=JSONManager.getasJsonObject(response.getMessage());
      JsonObject fav=responseJson.get("String_Node_Str").getAsJsonObject(), sub=responseJson.get("String_Node_Str").getAsJsonObject();
      int favCode=fav.get("String_Node_Str").getAsInt(), subCode=sub.get("String_Node_Str").getAsInt();
      if (subCode == 200) {
        if (notifications.isEmpty()) {
          subscriptionsTable.remove(key);
        }
 else         if (subscriptionsTable.exists(key)) {
          subscriptionsTable.update(key,new Subscription(user,modelKey,notifications));
        }
 else {
          subscriptionsTable.add(new Subscription(user,modelKey,notifications));
        }
      }
 else       if (subCode == 500) {
        Toast.makeText(context,String.format(context.getString(R.string.mytba_error),subCode,sub.get("String_Node_Str").getAsString()),Toast.LENGTH_SHORT).show();
      }
      if (favCode == 200) {
        if (!isFavorite) {
          favoritesTable.remove(key);
        }
 else         if (favoritesTable.exists(key)) {
        }
 else {
          favoritesTable.add(new Favorite(user,modelKey));
        }
      }
 else       if (favCode == 500) {
        Toast.makeText(context,String.format(context.getString(R.string.mytba_error),favCode,fav.get("String_Node_Str").getAsString()),Toast.LENGTH_SHORT).show();
      }
      return Result.SUCCESS;
    }
 catch (    IOException e) {
      Log.e(Constants.LOG_TAG,"String_Node_Str");
      e.printStackTrace();
      return Result.ERROR;
    }
  }
}