src/vs/workbench/api/common/extHostNotebookKernels.ts/ExtHostNotebookKernels/$acceptKernelMessageFromRenderer
class ExtHostNotebookKernels:	$acceptKernelMessageFromRenderer(handle: number, editorId: string, message: any): void {
		const obj = this._kernelData.get(handle);
		if (!obj) {
			// extension can dispose kernels in the meantime
			return;
		}

		const editor = this._extHostNotebook.getEditorById(editorId);
		obj.onDidReceiveMessage.fire(Object.freeze({ editor: editor.apiEditor, message }));
	}