fix(compiler-cli): don't report emit diagnostics when --noEmitOnError is off (#20063)

packages/compiler-cli/index.ts

@@ -22,3 +22,5 @@ export * from './src/perform_compile';
 // and usages in G3 are changed to `CompilerOptions`.
 export {CompilerOptions as AngularCompilerOptions} from './src/transformers/api';
 export {NgTools_InternalApi_NG_2 as __NGTOOLS_PRIVATE_API_2} from './src/ngtools_api';
+
+export {ngToTsDiagnostic} from './src/transformers/util';