How do I make autosizing custom cell?

I've followed the tutorial and guideline and stuff, finally managed to create a chatVC with my custom cell. However, there's this autosizing issue where I don't know how to make it work.

Setup:

```
final class ChatContentCVC: BaseChatViewController {
override var canBecomeFirstResponder: Bool { return false }
override func createChatInputView() -> UIView { return UIView() }

override func createPresenterBuilders() -> [ChatItemType: [ChatItemPresenterBuilderProtocol]] {
return [ChatMessageModel.type: [ChatMsgPresenterBuilder()]
}
}
```
Where `ChatMessageModel` & `ChatMsgPresenterBuilder` is my custom model & builder. Typpically, I don't want to inherit or import the `ChattoAdditions`, so I built my own text message cell, and it works, until...

The Presenter.
```
final class ChatMsgPresenter: ChatItemPresenterProtocol {

let msgModel: ChatMessageModel
private weak var sizingCell: ChatMsgCVCell?

init (msgModel: ChatMessageModel, sizingCell: ChatMsgCVCell) {
self.msgModel = msgModel
self.sizingCell = sizingCell
}

static func registerCells(_ collectionView: UICollectionView) {
let sending = ChatMsgCVCell.sendingCellId
let receiving = ChatMsgCVCell.receivingCellId
collectionView.register(UINib(nibName: sending, bundle: Bundle(for: self)), forCellWithReuseIdentifier: sending)
collectionView.register(UINib(nibName: receiving, bundle: Bundle(for: self)), forCellWithReuseIdentifier: receiving)
}

func dequeueCell(collectionView: UICollectionView, indexPath: IndexPath) -> UICollectionViewCell {

let cellId = msgModel.owner == .me ? ChatMsgCVCell.sendingCellId : ChatMsgCVCell.receivingCellId
return collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath)
}

func configureCell(_ cell: UICollectionViewCell, decorationAttributes: ChatItemDecorationAttributesProtocol?) {
guard let cell = cell as? ChatMsgCVCell else { return }
cell.fillData(msgModel)
}

var canCalculateHeightInBackground: Bool {
return false
}

```

Now's the tricky part and also the question of this issue: calculate cell's autosizing height
```
func heightForCell(maximumWidth width: CGFloat, decorationAttributes:
ChatItemDecorationAttributesProtocol?) -> CGFloat {
// How should I get dynamic sizing here?
// Should I cache the layout like ChattoAdditions' TextMessageCollectionViewCell?
// I've created my own sizingCell, but it doesn't seem to work.
// Also, using sizingCell might freeze the app if var canCalculateHeightInBackground = false
return 90 // hard code works okay, but not autosizing is a big problem.
}
```

Start with ChatItemPresenterProtocol and the custom ChatMsgPresenter implementation, especially heightForCell(maximumWidth:decorationAttributes:) and the sizingCell property. Compare this path with ChattoAdditions' TextMessageCollectionViewCell sizing behavior. Done means the custom cell returns its dynamic height instead of the hard-coded 90 without freezing background layout.

Written by the indexing model from the issue text.