Dear Maintainer,

I'm trying to build Xfce panel plugin which is written using Vala
language, and it fails because of missing Vala API files in
libxfce4panel-2.0-dev package.

Vala is the language which is widely used for writing applications
that use glib/gtk+ libraries.

I attach the patch for xfce4-panel package that can fix the issue.

The plugin I was trying to build:
https://gitlab.xfce.org/panel-plugins/xfce4-notes-plugin

Thank you!