Merge from vscode 8e0f348413f4f616c23a88ae30030efa85811973 (#6381)

* Merge from vscode 8e0f348413f4f616c23a88ae30030efa85811973

* disable strict null check

src/vs/workbench/api/browser/mainThreadMessageService.ts

@@ -90,7 +90,8 @@ export class MainThreadMessageService implements MainThreadMessageServiceShape {
 			// if promise has not been resolved yet, now is the time to ensure a return value
 			// otherwise if already resolved it means the user clicked one of the buttons
 			Event.once(messageHandle.onDidClose)(() => {
-				dispose(...primaryActions, ...secondaryActions);
+				dispose(primaryActions);
+				dispose(secondaryActions);
 				resolve(undefined);
 			});
 		});