Add PowerManagerInterface.

Hide all dbus stuff under the new interface, so that we can implement
a real power_manager for android in the future if needed.

Test: mma
Bug: 28800946

Change-Id: I26c883f4d0bc71f0410dfe4422b22bdd9df70575
diff --git a/power_manager_interface.h b/power_manager_interface.h
new file mode 100644
index 0000000..be059ec
--- /dev/null
+++ b/power_manager_interface.h
@@ -0,0 +1,47 @@
+//
+// Copyright (C) 2016 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_POWER_MANAGER_INTERFACE_H_
+#define UPDATE_ENGINE_POWER_MANAGER_INTERFACE_H_
+
+#include <memory>
+
+#include <base/macros.h>
+
+namespace chromeos_update_engine {
+
+class PowerManagerInterface {
+ public:
+  virtual ~PowerManagerInterface() = default;
+
+  // Request the power manager to restart the device. Returns true on success.
+  virtual bool RequestReboot() = 0;
+
+ protected:
+  PowerManagerInterface() = default;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(PowerManagerInterface);
+};
+
+namespace power_manager {
+// Factory function which create a PowerManager.
+std::unique_ptr<PowerManagerInterface> CreatePowerManager();
+}
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_POWER_MANAGER_INTERFACE_H_