fix(@ngtools/webpack): replace bootstrap code under Ivy unless running in JIT mode

The bootstrap code always needs to be replaced if not running in JIT mode as other wise the entire compiler will be pulled in because we will not replace the bootstrapping code to use `platform-browser` instead of `platform-browser-dynamic`.

Author: Alan Agius

packages/ngtools/webpack/src/angular_compiler_plugin.ts

@@ -948,13 +948,13 @@ export class AngularCompilerPlugin {
             this._normalizedLocale));
         }
 
-        if (this._useFactories) {
-          // Replace bootstrap in browser AOT.
+        if (!this._JitMode) {
+          // Replace bootstrap in browser non JIT Mode.
           this._transformers.push(replaceBootstrap(
             isAppPath,
             getEntryModule,
             getTypeChecker,
-            !!this._compilerOptions.enableIvy,
+            this._useFactories,
           ));
         }
       } else if (this._platform === PLATFORM.Server) {

packages/ngtools/webpack/src/transformers/replace_bootstrap.ts

@@ -17,7 +17,7 @@ export function replaceBootstrap(
   shouldTransform: (fileName: string) => boolean,
   getEntryModule: () => { path: string, className: string } | null,
   getTypeChecker: () => ts.TypeChecker,
-  enableIvy?: boolean,
+  useFactories = true,
 ): ts.TransformerFactory<ts.SourceFile> {
 
   const standardTransform: StandardTransform = function (sourceFile: ts.SourceFile) {
@@ -82,7 +82,7 @@ export function replaceBootstrap(
       let modulePath = `./${relativeEntryModulePath}`.replace(/\\/g, '/');
       let bootstrapIdentifier = 'bootstrapModule';
 
-      if (!enableIvy) {
+      if (useFactories) {
         className += 'NgFactory';
         modulePath += '.ngfactory';
         bootstrapIdentifier = 'bootstrapModuleFactory';

packages/ngtools/webpack/src/transformers/replace_bootstrap_spec.ts

@@ -52,7 +52,7 @@ describe('@ngtools/webpack transformers', () => {
       expect(tags.oneLine`${result}`).toEqual(tags.oneLine`${output}`);
     });
 
-    it('should replace bootstrap for Ivy without referencing ngFactory', () => {
+    it('should replace bootstrap without referencing ngFactory when useFactories is false', () => {
       const input = tags.stripIndent`
         import { enableProdMode } from '@angular/core';
         import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
@@ -87,7 +87,7 @@ describe('@ngtools/webpack transformers', () => {
         () => true,
         () => ({ path: '/project/src/app/app.module', className: 'AppModule' }),
         () => program.getTypeChecker(),
-        true,
+        false,
       );
       const result = transformTypescript(undefined, [transformer], program, compilerHost);