Add a screen to migrate filesystem encryption from eCryptfs to ext4 crypto.

chromeos/login/auth/login_performer.cc

Index: chromeos/login/auth/login_performer.cc
diff --git a/chromeos/login/auth/login_performer.cc b/chromeos/login/auth/login_performer.cc
index 11c96b9b1a90aa594247e645210126338cacd0af..6fa6aea3517f2e51e5cd76231a1f859b760ed89d 100644
--- a/chromeos/login/auth/login_performer.cc
+++ b/chromeos/login/auth/login_performer.cc
@@ -107,6 +107,15 @@ void LoginPerformer::OnPasswordChangeDetected() {
   }
 }
 
+void LoginPerformer::OnOldEncryptionDetected() {
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
+
+  if (delegate_)
+    delegate_->OnOldEncryptionDetected();
+  else
+    NOTREACHED();
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // LoginPerformer, public: