ash: Use SessionController instead of SessionStateDelegate

ash/shell/example_session_controller_client.h

Index: ash/shell/example_session_controller_client.h
diff --git a/ash/shell/example_session_controller_client.h b/ash/shell/example_session_controller_client.h
new file mode 100644
index 0000000000000000000000000000000000000000..1cdbd2f8343d5fc034a5996a9fd3421145bd1756
--- /dev/null
+++ b/ash/shell/example_session_controller_client.h
@@ -0,0 +1,38 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef ASH_SHELL_EXAMPLE_SESSION_CONTROLLER_CLIENT_H_
+#define ASH_SHELL_EXAMPLE_SESSION_CONTROLLER_CLIENT_H_
+
+#include "ash/common/test/test_session_controller_client.h"
+#include "base/macros.h"
+
+namespace ash {
+
+class SessionController;
+
+namespace shell {
+
+class ExampleSessionControllerClient
+    : public test::TestSessionControllerClient {
+ public:
+  explicit ExampleSessionControllerClient(SessionController* controller);
+  ~ExampleSessionControllerClient() override;
+
+  static ExampleSessionControllerClient* Get();
+
+  void Initialize();
+
+  // TestSessionControllerClient
+  void RequestLockScreen() override;
+  void UnlockScreen() override;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ExampleSessionControllerClient);
+};
+
+}  // namespace shell
+}  // namespace ash
+
+#endif  // ASH_SHELL_EXAMPLE_SESSION_CONTROLLER_CLIENT_H_