[gtk+] (6 commits) Non-fast-forward update to branch wip/cosimoc/combobox-gadget

[Cosimo Cecchi <cosimoc src gnome org>]

The branch 'wip/cosimoc/combobox-gadget' 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:

  b9999ca... Introduce GtkIcon private class
  0af5ec1... combobox: use GtkIcon to render button arrow

Commits added to the branch:

  11ad60d... flowbox: remove unused prelight code (*)
  cc50652... Adwaita: Fix overwrite cursors in entries (*)
  a231c15... Introduce GtkIcon private class
  2c5e7ec... combobox: use GtkIcon to render button arrow
  b2f36a2... combobox: remove unneeded check
  231ac90... combobox: trivial code cleanup

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