src/vs/editor/common/services/modelService.ts/ModelData/constructor
class ModelData:	constructor(
		model: TextModel,
		onWillDispose: (model: ITextModel) => void,
		onDidChangeLanguage: (model: ITextModel, e: IModelLanguageChangedEvent) => void
	) {
		this.model = model;

		this._languageSelection = null;
		this._languageSelectionListener = null;

		this._modelEventListeners.add(model.onWillDispose(() => onWillDispose(model)));
		this._modelEventListeners.add(model.onDidChangeLanguage((e) => onDidChangeLanguage(model, e)));
	}