src/vs/workbench/api/browser/mainThreadNotebookRenderers.ts/MainThreadNotebookRenderers/constructor
class MainThreadNotebookRenderers:	constructor(
		extHostContext: IExtHostContext,
		@INotebookRendererMessagingService private readonly messaging: INotebookRendererMessagingService,
	) {
		super();
		this.proxy = extHostContext.getProxy(ExtHostContext.ExtHostNotebookRenderers);
		this._register(messaging.onShouldPostMessage(e => {
			this.proxy.$postRendererMessage(e.editorId, e.rendererId, e.message);
		}));
	}