Add browser test for initial languages.

chrome/browser/chromeos/customization_document.h

Index: chrome/browser/chromeos/customization_document.h
diff --git a/chrome/browser/chromeos/customization_document.h b/chrome/browser/chromeos/customization_document.h
index 4322855ea0df753589e0ae5455b8f57d55a89baf..d3c89fb2350247b32c0bc7474339af6fc3b7fb65 100644
--- a/chrome/browser/chromeos/customization_document.h
+++ b/chrome/browser/chromeos/customization_document.h
@@ -329,6 +329,12 @@ class ServicesCustomizationDocument : public CustomizationDocument,
   DISALLOW_COPY_AND_ASSIGN(ServicesCustomizationDocument);
 };
 
+// In tests we need to override initial locale.
+void SetEnforceInitialLocaleForTesting(const char* locale);
+
+// In tests we need to override initial keyboard.
+void SetEnforceInitialKeyboardForTesting(const char* keyboard);
+
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_CUSTOMIZATION_DOCUMENT_H_