[libadwaita] (20 commits) Non-fast-forward update to branch wip/snwh/checks

[Alexander Mikhaylenko <alexm src gnome org>]

The branch 'wip/snwh/checks' 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:

  39bd4eb... checkbox experiments
  1cfde11... revert round checkbox
  a69bc98... abandon the borders idea
  a0c3346... abandon the borders idea further
  08815b1... got borders to work with highcontrast

Commits added to the branch:

  f9c418d... stylesheet: Fix paned separators (*)
  60b274c... toast-overlay: Set overflow=hidden (*)
  54802ae... demo: .content -> .boxed-list (*)
  ec8f377... stylesheet: Offer regular/bg/fg variants for error/success/ (*)
  0b4d8eb... stylesheet: Refresh treeview and columnview headers (*)
  d3aa3db... carousel: Animate in pixels rather than pages (*)
  f457b17... squeezer: Port to AdwAnimation (*)
  141a120... leaflet: Port mode transition to AdwAnimation (*)
  ac4890e... leaflet: Port child transitions to AdwAnimation (*)
  ae657c4... leaflet: Stop using get_allocated_width()/height() (*)
  7dec08e... swipeable: Stop using get_allocated_width()/height() (*)
  06c9d91... Remove GtkProgressTracker (*)
  155ebc9... tab-view: Fix needs-attention with non-inline tab bars (*)
  c468a22... stylesheet: Fix infobar colors (*)
  98f633b... stylesheet: Consistently use accent_color for entry focus (*)
  14c12b0... stylesheet: Use accent_color for rubberband selection (*)
  6f97e5c... stylesheet: Tweak tab needs-attention indicators (*)
  1636072... stylesheet: Use custom blue as accent_color in dark (*)
  cdcd6b4... stylesheet: Tweak check focus (*)
  fbe886b... stylesheet: Tweak check style

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