[vala] (14 commits) ...Make sure type check expression has valid type

[Jürg Billeter <juergbi src gnome org>]

Summary of changes:

  5cd3511... gtk+-2.0, gtk+-3.0: port lots of annotations from the GIR v (*)
  72b0e97... gtk+-3.0: Add type_ids and abstract annotations for classes (*)
  7c2b511... gtk+-3.0: port "struct" annotations from the GIR version (*)
  5b739e5... gtk+-2.0, gtk+-3.0: Hide non-public symbols (*)
  edd3c32... gtk+-2.0: port "struct" annotations from the GIR version (*)
  0bd8956... gtk+-2.0, gtk+-3.0: port more annotations from the GIR vers (*)
  b3629d8... gtk+-2.0, gtk+-3.0: more various fixes (*)
  3494c3f... gtk+-2.0, gtk+-3.0: Make Widget.get/set_parent compatible w (*)
  98ae401... gtk+-2.0, gtk+-3.0: Radio/ActionCallback are only vala-help (*)
  91a147c... gtk+-2.0, gtk+-3.0: Gtk.get_default_language is unowned (*)
  56f58c5... gtk+-2.0, gtk+-3.0: GtkCssProviderError/GtkPrintError are e (*)
  8514228... gtk+-2.0, gtk+-3.0: Fix gtk_target_list_find (*)
  09aba1e... Test error type check (*)
  57c7d28... Make sure type check expression has valid type (*)

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