[gtk] (12 commits) ...Merge branch 'wip/baedert/for-master' into 'master'

[Matthias Clasen <matthiasc src gnome org>]

Summary of changes:

  a77f8e8... cssprovider: Fix a memory leak in load_internal (*)
  d1c37c4... Add a gtk valgrind suppression file (*)
  4123c85... actionmuxer: Plug a memory leak (*)
  1459ca2... widget factory: Plug a memory leak (*)
  449c96f... widget: Unref previous transform (*)
  dbc49e7... transform: Fix identity transform fast paths (*)
  95f30fe... iconhelper: Try to avoid some save/restore calls (*)
  b062594... gl renderer: Properly clean up program state transforms (*)
  042f7d1... compare-render: Don't unref an invalid GFile (*)
  633172f... widget: Make queue_compute_expand() private (*)
  264d4ba... widget: Remove queue_resize_no_redraw (*)
  bda3c6c... Merge branch 'wip/baedert/for-master' into 'master'

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