src/vs/workbench/contrib/notebook/common/model/notebookTextModel.ts/NotebookTextModel/_bindCellContentHandler
class NotebookTextModel:	private _bindCellContentHandler(cell: NotebookCellTextModel, e: 'content' | 'language' | 'mime') {
		this._increaseVersionId(e === 'content');
		switch (e) {
			case 'content':
				this._eventEmitter.emit({ kind: NotebookCellsChangeType.ChangeCellContent, transient: false }, true);
				break;

			case 'language':
				this._eventEmitter.emit({ kind: NotebookCellsChangeType.ChangeLanguage, index: this._getCellIndexByHandle(cell.handle), language: cell.language, transient: false }, true);
				break;

			case 'mime':
				this._eventEmitter.emit({ kind: NotebookCellsChangeType.ChangeCellMime, index: this._getCellIndexByHandle(cell.handle), mime: cell.mime, transient: false }, true);
				break;
		}
	}