buffet: Stub for StartDevice method.

This introduces StartDevice method with stub implementation
and allows buffet_client to invoke it.

BUG=None
TEST=cros_workon_make buffet --test and manual.

Change-Id: I3f89ed3fc735c0521041484bb9fdebc43d9d4b79
Reviewed-on: https://chromium-review.googlesource.com/220771
Commit-Queue: Anton Muhin <antonm@chromium.org>
Tested-by: Anton Muhin <antonm@chromium.org>
Reviewed-by: Alex Vakulenko <avakulenko@chromium.org>
diff --git a/buffet/manager.cc b/buffet/manager.cc
index 10d36cf..01716f4 100644
--- a/buffet/manager.cc
+++ b/buffet/manager.cc
@@ -36,6 +36,9 @@
 void Manager::RegisterAsync(const AsyncEventSequencer::CompletionAction& cb) {
   chromeos::dbus_utils::DBusInterface* itf =
       dbus_object_.AddOrGetInterface(dbus_constants::kManagerInterface);
+  itf->AddMethodHandler(dbus_constants::kManagerStartDevice,
+                        base::Unretained(this),
+                        &Manager::HandleStartDevice);
   itf->AddMethodHandler(dbus_constants::kManagerCheckDeviceRegistered,
                         base::Unretained(this),
                         &Manager::HandleCheckDeviceRegistered);
@@ -68,6 +71,11 @@
   device_info_->Load();
 }
 
+void Manager::HandleStartDevice(chromeos::ErrorPtr* error) {
+  LOG(INFO) << "Received call to Manager.StartDevice()";
+  LOG(INFO) << "Not implemented";
+}
+
 std::string Manager::HandleCheckDeviceRegistered(chromeos::ErrorPtr* error) {
   LOG(INFO) << "Received call to Manager.CheckDeviceRegistered()";
   std::string device_id;