Returns approximate number of messages of the specified type in the chat
| chat_id |
Identifier of the chat in which to count messages |
| filter |
Filter for message content; searchMessagesFilterEmpty is unsupported in this function |
| saved_messages_topic_id |
If not 0, only messages in the specified Saved Messages topic will be counted; pass 0 to count all messages, or for chats other than Saved Messages |
| return_local |
Pass true to get the number of messages without sending network requests, or -1 if the number of messages is unknown locally |