src/vs/workbench/contrib/notebook/browser/notebookEditorServiceImpl.ts/NotebookEditorWidgetService/removeEditorDecorationType
class NotebookEditorWidgetService:	removeEditorDecorationType(key: string): void {
		this._decorationOptionProviders.delete(key);
		this.listNotebookEditors().forEach(editor => editor.removeEditorDecorations(key));
	}