src/vs/workbench/services/textMate/browser/textMateWorker.ts/TextMateWorkerModel/_resetTokenization
class TextMateWorkerModel:	private _resetTokenization(): void {
		this._tokenizationStateStore = null;

		const languageId = this._languageId;
		const encodedLanguageId = this._encodedLanguageId;
		this._worker.getOrCreateGrammar(languageId, encodedLanguageId).then((r) => {
			if (this._isDisposed || languageId !== this._languageId || encodedLanguageId !== this._encodedLanguageId || !r) {
				return;
			}

			if (r.grammar) {
				const tokenizationSupport = new TMTokenization(r.grammar, r.initialState, false);
				this._tokenizationStateStore = new TokenizationStateStore(tokenizationSupport, tokenizationSupport.getInitialState());
			} else {
				this._tokenizationStateStore = null;
			}
			this._ensureTokens();
		});
	}