[gtk] (26 commits) Non-fast-forward update to branch stack-fixes

[Matthias Clasen <matthiasc src gnome org>]

The branch 'stack-fixes' 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:

  fa447c6... gtk-demo: Fix the sidebar demo
  32eb891... gtk: Add GtkSelectionModel
  5b2de24... gtk: Add GtkSingleSelection
  24feaa6... testsuite: Add selection model tests
  7ab30c9... testsuite: omit some selection properties
  3cd52ce... stack: Add a GtkStackPage::visible property
  30987fc... stack: Provide a selection model
  544d473... stack switcher: Use the selection model
  b14a0a8... a11y tests: Adapt to changes
  37c741f... stack sidebar: Use the selection model
  52c5b4b... stack: Drop the position property

Commits added to the branch:

  7863224... app icons: use new style (*)
  a72b91e... Fix icon installation (*)
  6959e8c... typo correction (*)
  e1f903c... Update Galician translation (*)
  81f88ba... flatpak: Stop renaming icons (*)
  131c225... Merge branch 'wip/jimmac/app-icons' into 'master' (*)
  9bfdcfb... Update Galician translation (*)
  f79ded3... Update Finnish translation (*)
  2146fd2... GdkDisplay: Use a GQueue for the events queue (*)
  d1ea591... rendericon: Ignore transparent icons (*)
  14feafe... window: Remove GList link directly (*)
  ea55458... glglyphcache: Remove surface member from dirty glyph (*)
  a872c41... glglyphcache: Fix dropping caches unnecessarily (*)
  bee5183... demo: Fix fishbowl default togglebutton state (*)
  e0f8b8e... Merge branch 'fix-typo' into 'master' (*)
  317b9e6... gtk-demo: Fix the sidebar demo
  16024fb... gtk: Add GtkSelectionModel
  30386bb... gtk: Add GtkSingleSelection
  dcdec4b... testsuite: Add selection model tests
  ccb0a0f... testsuite: omit some selection properties
  dc0750f... stack: Add a GtkStackPage::visible property
  7b08d13... stack: Provide a selection model
  8595665... stack switcher: Use the selection model
  976664c... a11y tests: Adapt to changes
  9255a12... stack sidebar: Use the selection model
  916508f... stack: Drop the position property

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