Migrate Channel.UserBelongsToChannels to Sync by default (#11269)

* Migrate Channel.UserBelongsToChannels to Sync by default

* Address comments

store/sqlstore/channel_store.go

@@ -2634,26 +2634,22 @@ func (s SqlChannelStore) GetChannelsBatchForIndexing(startTime, endTime int64, l
 	return channels, nil
 }
 
-func (s SqlChannelStore) UserBelongsToChannels(userId string, channelIds []string) store.StoreChannel {
-	return store.Do(func(result *store.StoreResult) {
-		query := s.getQueryBuilder().
-			Select("Count(*)").
-			From("ChannelMembers").
-			Where(sq.And{
-				sq.Eq{"UserId": userId},
-				sq.Eq{"ChannelId": channelIds},
-			})
+func (s SqlChannelStore) UserBelongsToChannels(userId string, channelIds []string) (bool, *model.AppError) {
+	query := s.getQueryBuilder().
+		Select("Count(*)").
+		From("ChannelMembers").
+		Where(sq.And{
+			sq.Eq{"UserId": userId},
+			sq.Eq{"ChannelId": channelIds},
+		})
 
-		queryString, args, err := query.ToSql()
-		if err != nil {
-			result.Err = model.NewAppError("SqlChannelStore.UserBelongsToChannels", "store.sql_channel.user_belongs_to_channels.app_error", nil, err.Error(), http.StatusInternalServerError)
-			return
-		}
-		c, err := s.GetReplica().SelectInt(queryString, args...)
-		if err != nil {
-			result.Err = model.NewAppError("SqlChannelStore.UserBelongsToChannels", "store.sql_channel.user_belongs_to_channels.app_error", nil, err.Error(), http.StatusInternalServerError)
-			return
-		}
-		result.Data = c > 0
-	})
+	queryString, args, err := query.ToSql()
+	if err != nil {
+		return false, model.NewAppError("SqlChannelStore.UserBelongsToChannels", "store.sql_channel.user_belongs_to_channels.app_error", nil, err.Error(), http.StatusInternalServerError)
+	}
+	c, err := s.GetReplica().SelectInt(queryString, args...)
+	if err != nil {
+		return false, model.NewAppError("SqlChannelStore.UserBelongsToChannels", "store.sql_channel.user_belongs_to_channels.app_error", nil, err.Error(), http.StatusInternalServerError)
+	}
+	return c > 0, nil
 }