ChromeOS cryptohome should be able to use gaia id as user identifier.

chrome/browser/chromeos/login/login_browsertest.cc

Index: chrome/browser/chromeos/login/login_browsertest.cc
diff --git a/chrome/browser/chromeos/login/login_browsertest.cc b/chrome/browser/chromeos/login/login_browsertest.cc
index d1d248e77b4b97ae1fc1a4fb634a5a658daffe51..bd7b287a889082eb3bad83c6c913bd5954c8eb1e 100644
--- a/chrome/browser/chromeos/login/login_browsertest.cc
+++ b/chrome/browser/chromeos/login/login_browsertest.cc
@@ -161,8 +161,8 @@ class LoginTest : public LoginManagerTest {
 
     StartGaiaAuthOffline();
 
-    UserContext user_context(AccountId::FromUserEmail(kTestUser));
-    user_context.SetGaiaID(kGaiaId);
+    UserContext user_context(
+        AccountId::FromUserEmailGaiaId(kTestUser, kGaiaId));
     user_context.SetKey(Key(kPassword));
     SetExpectedCredentials(user_context);
   }