3.5.12 (unstable):

Gtk:
* Added the LevelBar widget.
  (Murray Cumming)
* Application:
  - Added get_active_window().
    (Murray Cumming)
  - Don't call add_window() before the application is registered.
    (Kjell Ahlstedt) Bug #681323 (Gregory Martin)
* CellRendererText: Added the placeholder_text property.
* Entry: Add input purpose and input hints methods.
* MenuButton: Added get/set_popup(), deprecated get/set_menu().
* Settings: Deprecate the gtk-touchscreen-property.
* TextView: Added input purpose and input hints methods.
* Widget: Added insert_action_group().
  (Murray Cumming)

Documentation:
* Show the get_type() methods in the API documentation.
  (Murray Cumming) Bug #670212 (Mark Vender).