Do not try to enroll past OOBE/enrollment.

chrome/browser/chromeos/policy/device_cloud_policy_initializer.cc

Index: chrome/browser/chromeos/policy/device_cloud_policy_initializer.cc
diff --git a/chrome/browser/chromeos/policy/device_cloud_policy_initializer.cc b/chrome/browser/chromeos/policy/device_cloud_policy_initializer.cc
index 7004daf82e9783461b5873c214b5284fda264e46..464a4f96a59fc3cd7d0b04adcf1c0faedb3677bf 100644
--- a/chrome/browser/chromeos/policy/device_cloud_policy_initializer.cc
+++ b/chrome/browser/chromeos/policy/device_cloud_policy_initializer.cc
@@ -149,7 +149,13 @@ EnrollmentConfig DeviceCloudPolicyInitializer::GetPrescribedEnrollmentConfig()
       break;
   }
 
+  // If OOBE is done and we are not enrolled, make sure we only try interactive
+  // enrollment.
   const bool oobe_complete = local_state_->GetBoolean(prefs::kOobeComplete);
+  if (oobe_complete &&
+      config.auth_mechanism == EnrollmentConfig::AUTH_MECHANISM_BEST_AVAILABLE)
+    config.auth_mechanism = EnrollmentConfig::AUTH_MECHANISM_INTERACTIVE;

[xiyuan, 2016/09/16 07:49:13]

nit: wrap with {} since the condition takes more than one line.

+  // If OOBE is done and we are enrolled, check for need to recover enrollment.
   if (oobe_complete && install_attributes_->IsEnterpriseDevice()) {
     // Regardless what mode is applicable, the enrollment domain is fixed.
     config.management_domain = install_attributes_->GetDomain();