feat(@schematics/angular): add migration ensure that tslib is installed (#15800)

Related to: angular/angular#32167

Author: alan-agius4

packages/schematics/angular/migrations/update-9/add-tslib.ts

@@ -0,0 +1,21 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+import { Rule } from '@angular-devkit/schematics';
+import { NodeDependencyType, addPackageJsonDependency, removePackageJsonDependency } from '../../utility/dependencies';
+import { latestVersions } from '../../utility/latest-versions';
+
+export function addTsLib(): Rule {
+  return host => {
+    removePackageJsonDependency(host, 'tslib');
+    addPackageJsonDependency(host, {
+        name: 'tslib',
+        version: latestVersions.TsLib,
+        type: NodeDependencyType.Default,
+    });
+  };
+}

packages/schematics/angular/migrations/update-9/index.ts

@@ -8,6 +8,7 @@
 
 import { Rule, chain } from '@angular-devkit/schematics';
 import { NodePackageInstallTask } from '@angular-devkit/schematics/tasks';
+import { addTsLib } from './add-tslib';
 import { updateLibraries } from './ivy-libraries';
 import { updateNGSWConfig } from './ngsw-config';
 import { removeTsickle } from './remove-tsickle';
@@ -26,6 +27,7 @@ export default function(): Rule {
       updateDependencies(),
       updateServerMainFile(),
       removeTsickle(),
+      addTsLib(),
       (tree, context) => {
         const packageChanges = tree.actions.some(a => a.path.endsWith('/package.json'));
         if (packageChanges) {

packages/schematics/angular/migrations/update-9/update-dependencies.ts

@@ -5,12 +5,12 @@
  * Use of this source code is governed by an MIT-style license that can be
  * found in the LICENSE file at https://angular.io/license
  */
-import { Tree } from '@angular-devkit/schematics';
+import { Rule } from '@angular-devkit/schematics';
 import { addPackageJsonDependency, getPackageJsonDependency } from '../../utility/dependencies';
 import { latestVersions } from '../../utility/latest-versions';
 
-export function updateDependencies() {
-  return (host: Tree) => {
+export function updateDependencies(): Rule {
+  return host => {
     const dependenciesToUpdate: Record<string, string> = {
       '@angular/pwa': latestVersions.AngularPWA,
       '@angular-devkit/build-angular': latestVersions.DevkitBuildAngular,