[vala] (3 commits) Non-fast-forward update to branch wip/ricotz

[Rico Tzschichholz <ricotz src gnome org>]

The branch 'wip/ricotz' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  ea24ad6... vala: Pass through the format-literal
  2fb6a88... codegen: Append G_GNUC_FORMAT attribute to FormatArg functi

Commits added to the branch:

  368779f... tests: Enable -Werror=format-nonliteral (*)
  f4e0b1a... codegen: Add G_GNUC_FORMAT attribute for FormatArg function (*)
  e059068... tests: More cases of FormatArg functions

(*) This commit already existed in another branch; no separate mail sent