[Sync] Generalize StringOrdinal to handle ordinal_in_parent field

chrome/browser/extensions/extension_browsertest.cc

Index: chrome/browser/extensions/extension_browsertest.cc
diff --git a/chrome/browser/extensions/extension_browsertest.cc b/chrome/browser/extensions/extension_browsertest.cc
index a529281996e25fd0d6fac2aeced6259b3091fe07..7432b42f40155f1cf36ae0bcb5df89db4f171d6f 100644
--- a/chrome/browser/extensions/extension_browsertest.cc
+++ b/chrome/browser/extensions/extension_browsertest.cc
@@ -37,6 +37,7 @@
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/test/browser_test_utils.h"
+#include "sync/api/string_ordinal.h"
 
 using extensions::Extension;
 using extensions::ExtensionCreator;
@@ -128,7 +129,7 @@ const Extension* ExtensionBrowserTest::LoadExtensionWithFlags(
   // are set up with the defaults.
   service->extension_prefs()->OnExtensionInstalled(
       extension, Extension::ENABLED, false,
-      StringOrdinal::CreateInitialOrdinal());
+      syncer::StringOrdinal::CreateInitialOrdinal());
 
   // Toggling incognito or file access will reload the extension, so wait for
   // the reload and grab the new extension instance. The default state is