Fix self cert tests

Author: DonJayamanne

news/3 Code Health/10447.md

@@ -0,0 +1 @@
+Enable the `Selft Cert` tests for Notebooks.

src/client/common/errors/errorUtils.ts

@@ -1,6 +1,8 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
+import { EOL } from 'os';
+
 // tslint:disable-next-line:no-stateless-class no-unnecessary-class
 export class ErrorUtils {
     public static outputHasModuleNotInstalledError(moduleName: string, content?: string): boolean {
@@ -11,3 +13,15 @@ export class ErrorUtils {
             : false;
     }
 }
+
+/**
+ * Wraps an error with a custom error message, retaining the call stack information.
+ */
+export class WrappedError extends Error {
+    constructor(message: string, originalException: Error) {
+        super(message);
+        // Retain call stack that trapped the error and rethrows this error.
+        // Also retain the call stack of the original error.
+        this.stack = `${new Error('').stack}${EOL}${EOL}${originalException.stack}`;
+    }
+}