[gtk] (6 commits) Non-fast-forward update to branch wip/baedert/for-master

[Timm Bäder <baedert src gnome org>]

The branch 'wip/baedert/for-master' 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:

  0a662b5... gl renderer: Use scale_x and scale_y everywhere
  4bc276d... gl renderer: Ignore crossfades between equal texture nodes

Commits added to the branch:

  0dff89d... Revert "theme: Round all window corners" (*)
  67d7e20... Update POTFILES.in (*)
  894f893... Merge branch 'revert-round-windows' into 'master' (*)
  ca91cae... gl renderer: Use scale_x and scale_y everywhere
  9a99ab5... gl renderer: Ignore crossfades between equal texture nodes
  c4634b4... gl renderer: Fix rendering clipped blurred inset shadow nod

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