Remove unused user email argument from nss_util.

crypto/scoped_test_nss_chromeos_user.cc

Index: crypto/scoped_test_nss_chromeos_user.cc
diff --git a/crypto/scoped_test_nss_chromeos_user.cc b/crypto/scoped_test_nss_chromeos_user.cc
index 20eadf49db86444315ebf9a409ac6e52a2f32277..aec25d8dff0c397ee7ebb50a876665d8f6037775 100644
--- a/crypto/scoped_test_nss_chromeos_user.cc
+++ b/crypto/scoped_test_nss_chromeos_user.cc
@@ -17,8 +17,8 @@ ScopedTestNSSChromeOSUser::ScopedTestNSSChromeOSUser(
     return;
   // This opens a software DB in the given folder. In production code that is in
   // the home folder, but for testing the temp folder is used.
-  constructed_successfully_ = InitializeNSSForChromeOSUser(
-      username_hash, username_hash, temp_dir_.path());
+  constructed_successfully_ =
+      InitializeNSSForChromeOSUser(username_hash, temp_dir_.path());
 }
 
 ScopedTestNSSChromeOSUser::~ScopedTestNSSChromeOSUser() {