[gnome-builder] vala-pack: add ide-vala-pipeline-addin.vala to meson.build

[Christian Hergert <chergert src gnome org>]

commit 843208e539707bd1a84a4878c722c5f96cd42f4d
Author: Christian Hergert <chergert redhat com>
Date:   Thu Mar 2 15:54:25 2017 -0800

    vala-pack: add ide-vala-pipeline-addin.vala to meson.build
    
    This got out of sync when fixing 779426.

 plugins/vala-pack/meson.build |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/plugins/vala-pack/meson.build b/plugins/vala-pack/meson.build
index 769adad..2e667b0 100644
--- a/plugins/vala-pack/meson.build
+++ b/plugins/vala-pack/meson.build
@@ -62,6 +62,7 @@ vala_pack_sources = [
   'ide-vala-indenter.vala',
   'ide-vala-index.vala',
   'ide-vala-locator.vala',
+  'ide-vala-pipeline-addin.vala',
   'ide-vala-preferences-addin.vala',
   'ide-vala-source-file.vala',
   'ide-vala-symbol-resolver.vala',