refactor: rewrite private export using the ɵ prefix

modules/@angular/platform-browser/testing/browser_util.ts

@@ -7,9 +7,9 @@
  */
 
 import {NgZone} from '@angular/core';
+import {ɵgetDOM as getDOM} from '@angular/platform-browser';
 
 import {global} from './facade/lang';
-import {getDOM} from './private_import_platform-browser';
 
 export let browserDetection: BrowserDetection;
 
@@ -136,4 +136,4 @@ export function stringifyElement(el: any /** TODO #9100 */): string {
 
 export function createNgZone(): NgZone {
   return new NgZone({enableLongStackTrace: true});
-}
+}