fix(@angular-devkit/build-angular): downlevel iteration during differential loading

clydin · dgp1130 · commit 574e76e2dac2 · 2019-11-20T08:38:33.000-08:00
Closes #16229
diff --git a/packages/angular_devkit/build_angular/src/utils/process-bundle.ts b/packages/angular_devkit/build_angular/src/utils/process-bundle.ts
@@ -107,6 +107,7 @@ export async function process(options: ProcessBundleOptions): Promise<ProcessBun
     const transformResult = transpileModule(sourceCode, {
       fileName: downlevelFilename,
       compilerOptions: {
+        downlevelIteration: true,
         sourceMap: !!sourceMap,
         target: ScriptTarget.ES5,
       },
