[Vala] plank-config.c generated by Vala failed to include config.h

[Leslie Zhai <xiangzhai83 gmail com>]

Hi Vala developers,

I am a newbie of Vala, and we tried to add gettext support for Plank 
Config https://github.com/AOSC-Dev/Plank-Config A tool to config Plank Dock.

When make, the errors shown as below:

#error You must define GETTEXT_PACKAGE before including gi18n-lib.h. Did 
you forget to include config.h?

And I checked the plank-config.c generated by Vala, there is NO #include 
<config.h> at all!

Then I googled with Vala include config.h beform gi18n.h, it suggested 
as https://bugzilla.gnome.org/show_bug.cgi?id=618931
Indeed I added some GETTEXT relatived stuff 
https://github.com/AOSC-Dev/Plank-Config/commit/40a348a0669724fe7c56fe296000844f1a8e9ef4
But it still failed ;(

Do I need to use -X '-include config.h' for Makefile.am? 
https://github.com/AOSC-Dev/Plank-Config/blob/40a348a0669724fe7c56fe296000844f1a8e9ef4/Makefile.am#L11 

please someone give me some advice, thanks a lot!

--
Regards
Leslie Zhai
a KDE developer