refactor(@ngtools/webpack): simplify vfs webpack integration

Author: clydin

packages/@ngtools/webpack/src/angular_compiler_plugin.ts

@@ -599,19 +599,21 @@ export class AngularCompilerPlugin implements Tapable {
       this._donePromise = null;
     });
 
-    // TODO: consider if it's better to remove this plugin and instead make it wait on the
-    // VirtualFileSystemDecorator.
     compiler.plugin('after-resolvers', (compiler: any) => {
-      // Virtual file system.
-      // Wait for the plugin to be done when requesting `.ts` files directly (entry points), or
-      // when the issuer is a `.ts` or `.ngfactory.js` file.
-      compiler.resolvers.normal.plugin('before-resolve', (request: any, cb: () => void) => {
-        if (this.done && (request.request.endsWith('.ts')
-          || (request.context.issuer && /\.ts|ngfactory\.js$/.test(request.context.issuer)))) {
-          this.done.then(() => cb(), () => cb());
-        } else {
-          cb();
-        }
+      compiler.plugin('normal-module-factory', (nmf: any) => {
+        // Virtual file system.
+        // TODO: consider if it's better to remove this plugin and instead make it wait on the
+        // VirtualFileSystemDecorator.
+        // Wait for the plugin to be done when requesting `.ts` files directly (entry points), or
+        // when the issuer is a `.ts` or `.ngfactory.js` file.
+        nmf.plugin('before-resolve', (request: any, callback: any) => {
+          if (this.done && (request.request.endsWith('.ts')
+              || (request.context.issuer && /\.ts|ngfactory\.js$/.test(request.context.issuer)))) {
+            this.done.then(() => callback(null, request), () => callback(null, request));
+          } else {
+            callback(null, request);
+          }
+        });
       });
     });