[gtk] (8 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:

  92092c5... Add a gtk valgrind suppression file
  1d0709b... actionmuxer: Plug a memory leak
  1499b7c... widget factory: Plug a memory leak
  2dbe06b... widget: Unref previous transform
  00a9d50... suppression file: Add rule for media extension gio modules
  06d0bdb... transform: Fix identity transform fast paths
  6f1fc95... iconhelper: Try to avoid some save/restore calls

Commits added to the branch:

  3b1fe89... Add a gtk valgrind suppression file
  b5ed260... actionmuxer: Plug a memory leak
  92bd798... widget factory: Plug a memory leak
  3d63918... widget: Unref previous transform
  d68bb72... suppression file: Add rule for media extension gio modules
  a67ce43... transform: Fix identity transform fast paths
  52a85ff... iconhelper: Try to avoid some save/restore calls
  4713fba... gl renderer: Properly clean up program state transforms