src/vs/workbench/browser/parts/editor/editorStatus.ts/EditorStatus/onLanguageChange
class EditorStatus:	private onLanguageChange(editorWidget: ICodeEditor | undefined, editorInput: EditorInput | undefined): void {
		const info: StateDelta = { type: 'languageId', languageId: undefined };

		// We only support text based editors
		if (editorWidget && editorInput && toEditorWithLanguageSupport(editorInput)) {
			const textModel = editorWidget.getModel();
			if (textModel) {
				const languageId = textModel.getLanguageId();
				info.languageId = withNullAsUndefined(this.languageService.getLanguageName(languageId));
			}
		}

		this.updateState(info);
	}