[glib] (3 commits) Non-fast-forward update to branch wip/chergert/marshall-matters

[Philip Withnall <pwithnall src gnome org>]

The branch 'wip/chergert/marshall-matters' 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:

  0897a18... gsignal: update documentation about va_marshaller
  6327afb... gio: ensure default va_marshaller is used
  23d6a8e... gio: remove use of generic marshaller from GIO objects

Commits added to the branch:

  966df9c... gsignal: update documentation about va_marshaller
  046f47e... gio: ensure default va_marshaller is used
  4a28544... gio: remove use of generic marshaller from GIO objects