buffet: Remove D-Bus between CloudDelegate and Buffet

Now code runs in the same process so no need in IPC.

BUG=brillo:1161
TEST=`FEATURES=test emerge-gizmo buffet`

Change-Id: Ia23551b335cae9051948b62b6e15a2d2e3d4d106
Reviewed-on: https://chromium-review.googlesource.com/276603
Reviewed-by: Alex Vakulenko <avakulenko@chromium.org>
Commit-Queue: Vitaly Buka <vitalybuka@chromium.org>
Tested-by: Vitaly Buka <vitalybuka@chromium.org>
diff --git a/buffet/device_registration_info.h b/buffet/device_registration_info.h
index 9e8a8b0..52187ef 100644
--- a/buffet/device_registration_info.h
+++ b/buffet/device_registration_info.h
@@ -62,6 +62,10 @@
   void AddOnRegistrationChangedCallback(
       const OnRegistrationChangedCallback& callback);
 
+  // Add callback to listen for changes in config.
+  void AddOnConfigChangedCallback(
+      const BuffetConfig::OnChangedCallback& callback);
+
   // Returns the authorization HTTP header that can be used to talk
   // to GCD server for authenticated device communication.
   // Make sure ValidateAndRefreshAccessToken() is called before this call.