[vala] (4 commits) Non-fast-forward update to branch wip/housekeeping

[Rico Tzschichholz <ricotz src gnome org>]

The branch 'wip/housekeeping' 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:

  a9c1d01... codegen: Simplify get_signal_canonical_constant()
  4da8531... codegen: Simplify get_enum_value_canonical_cconstant()
  410aa5f... Fix deprecation of class/struct fields

Commits added to the branch:

  892e1fb... glib-2.0: Add simple fast-path to string.replace()
  aa0e857... codegen: Simplify get_signal_canonical_constant()
  1145e7f... codegen: Simplify get_enum_value_canonical_cconstant()
  b0e7db9... Fix deprecation of class/struct fields