build: produce metadata bundles for @angular modules (#14509)

Closes #14509

modules/@angular/router/index.ts

@@ -6,11 +6,9 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-/**
- * @module
- * @description
- * Entry point for all public APIs of the router package.
- */
-export * from './src/index';
+// This file is not used to build this module. It is only used during editing
+// by the TypeScript language serivce and during build for verifcation. `ngc`
+// replaces this file with production index.ts when it rewrites private symbol
+// names.
 
-// This file only reexports content of the `src` folder. Keep it that way.
+export * from './public_api';

modules/@angular/router/public_api.ts

@@ -0,0 +1,16 @@
+/**
+ * @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
+ */
+
+/**
+ * @module
+ * @description
+ * Entry point for all public APIs of the router package.
+ */
+export * from './src/index';
+
+// This file only reexports content of the `src` folder. Keep it that way.

modules/@angular/router/src/index.ts

@@ -14,6 +14,7 @@ export {RouterOutlet} from './directives/router_outlet';
 export {CanActivate, CanActivateChild, CanDeactivate, CanLoad, Resolve} from './interfaces';
 export {DetachedRouteHandle, RouteReuseStrategy} from './route_reuse_strategy';
 export {Event, NavigationCancel, NavigationEnd, NavigationError, NavigationExtras, NavigationStart, Router, RoutesRecognized} from './router';
+export {ROUTES} from './router_config_loader';
 export {ExtraOptions, ROUTER_CONFIGURATION, ROUTER_INITIALIZER, RouterModule, provideRoutes} from './router_module';
 export {RouterOutletMap} from './router_outlet_map';
 export {NoPreloading, PreloadAllModules, PreloadingStrategy, RouterPreloader} from './router_preloader';
@@ -22,4 +23,5 @@ export {PRIMARY_OUTLET, Params} from './shared';
 export {UrlHandlingStrategy} from './url_handling_strategy';
 export {DefaultUrlSerializer, UrlSegment, UrlSegmentGroup, UrlSerializer, UrlTree} from './url_tree';
 export {VERSION} from './version';
+
 export * from './private_export'

modules/@angular/router/src/router_config_loader.ts

@@ -18,6 +18,7 @@ import {flatten, wrapIntoObservable} from './utils/collection';
 
 
 /**
+ * @docsNotRequired
  * @experimental
  */
 export const ROUTES = new InjectionToken<Route[][]>('ROUTES');

modules/@angular/router/tsconfig-build.json

@@ -24,10 +24,12 @@
     "skipLibCheck": true
   },
   "files": [
-    "index.ts"
+    "public_api.ts"
   ],
   "angularCompilerOptions": {
     "annotateForClosureCompiler": true,
-    "strictMetadataEmit": true
+    "strictMetadataEmit": true,
+    "bundleIndex": "index",
+    "importAs": "@angular/router"
   }
 }