[gtk] (7 commits) Non-fast-forward update to branch matthiasc/for-master

[Matthias Clasen <matthiasc src gnome org>]

The branch 'matthiasc/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:

  62d62cd... columnview: Fix some issues with column resizing
  c1fdc6d... columview: Implement double-click to reset headers

Commits added to the branch:

  a88e5a5... columnview: Fix some issues with column resizing
  39baf4f... columnview: Fix more issues with column resizing
  1976df1... columnview: Make resize cursors reliable
  98b66ac... columview: Implement double-click to reset headers
  25d0fb4... columview: Make resize area a bit larger
  f3fe181... Adwaita: Put column separators on the left
  81ee273... columnview: Make right-aligned content work