That will allow easier updates in the future to ensure right vala version is detected and USED when compiling Thanks
*pdfpc-4.0.0-r1 (07 Jul 2015) 07 Jul 2015; Manuel Rüger <mrueg@gentoo.org> +pdfpc-4.0.0-r1.ebuild, -pdfpc-4.0.0.ebuild: Use vala.eclass