[gtk] (11 commits) Non-fast-forward update to branch wip/exalm/separator

[Alexander Mikhaylenko <alexm src gnome org>]

The branch 'wip/exalm/separator' 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:

  f3add9f... demo: Use .sidebar style class on the separator
  39d6b75... theme: Force 0 padding on separator.sidebar

Commits added to the branch:

  4660132... properly set ScaleButton's parent_class (*)
  47d5728... Merge branch 'scalebutton' into 'master' (*)
  8e81cbe... stacksidebar: Add missing .navigation-sidebar to the inner  (*)
  40f2b49... Adwaita: Make treeexpander styling generic (*)
  9828756... Adwaita: Move placessidebar-specific sizing from .navigatio (*)
  179fc68... Adwaita: Fix some sidebar sizing (*)
  bd0d75e... Adwaita: Make sidebar row styling better (*)
  61dcb68... Adwaita: Unify sidebar background-color (*)
  56eac4f... gtk-demo: Add .sidebar style class in the main window (*)
  3e996f6... icon-browser: Add .sidebar style class in the main window (*)
  3560f72... theme: Force 0 padding on separator.sidebar

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