prepare for removing proxy kernel.

src/vs/workbench/api/common/extHost.api.impl.ts

@@ -1320,6 +1320,7 @@ export function createApiFactoryAndRegisterActors(accessor: ServicesAccessor): I
 			NotebookCellOutputItem: extHostTypes.NotebookCellOutputItem,
 			NotebookCellStatusBarItem: extHostTypes.NotebookCellStatusBarItem,
 			NotebookControllerAffinity: extHostTypes.NotebookControllerAffinity,
+			NotebookControllerState: extHostTypes.NotebookControllerState,
 			PortAttributes: extHostTypes.PortAttributes,
 			LinkedEditingRanges: extHostTypes.LinkedEditingRanges,
 			TestResultState: extHostTypes.TestResultState,

src/vs/workbench/api/common/extHost.protocol.ts

@@ -970,6 +970,11 @@ export interface MainThreadNotebookDocumentsShape extends IDisposable {
 	$trySaveNotebook(uri: UriComponents): Promise<boolean>;
 }
 
+export enum NotebookControllerState {
+	Idle = 1,
+	Connecting = 2
+}
+
 export interface INotebookKernelDto2 {
 	id: string;
 	notebookType: string;
@@ -979,6 +984,7 @@ export interface INotebookKernelDto2 {
 	detail?: string;
 	description?: string;
 	kind?: string;
+	state?: NotebookControllerState;
 	supportedLanguages?: string[];
 	supportsInterrupt?: boolean;
 	supportsExecutionOrder?: boolean;

src/vs/workbench/api/common/extHostNotebookKernels.ts

@@ -196,6 +196,15 @@ export class ExtHostNotebookKernels implements ExtHostNotebookKernelsShape {
 			get rendererScripts() {
 				return data.preloads ? data.preloads.map(extHostTypeConverters.NotebookRendererScript.to) : [];
 			},
+			get state() {
+				checkProposedApiEnabled(extension, 'notebookProxyController');
+				return data.state;
+			},
+			set state(value) {
+				checkProposedApiEnabled(extension, 'notebookProxyController');
+				data.state = value;
+				_update();
+			},
 			get executeHandler() {
 				return _executeHandler;
 			},

src/vs/workbench/api/common/extHostTypes.ts

@@ -3369,6 +3369,11 @@ export class NotebookRendererScript {
 	}
 }
 
+export enum NotebookControllerState {
+	Idle = 1,
+	Connecting = 2
+}
+
 //#endregion
 
 //#region Timeline