[gtk] (10 commits) ...Merge branch 'matthiasc/for-master' into 'master'

[Matthias Clasen <matthiasc src gnome org>]

Summary of changes:

  4f5e3b7... gtk-demo: Improve an error message (*)
  19c6ef3... bookmarksmanager: Load bookmarks initially (*)
  2d5b447... placessidebar: We're not a listbox anymore (*)
  4eaf08e... placessidebar: Fix bookmarks dnd (*)
  e18de29... placessidebar: Fix the bookmark drag icon (*)
  dbbc9b5... placessidebar: Fix dnd cancellation (*)
  57a213a... gtk-demo: Fix iconscroll colors (*)
  1128831... gtk-demo: Fix iconscroll complex text (*)
  c6a7b39... Remove deprecation guards around gtk_window_present (*)
  d642bfc... Merge branch 'matthiasc/for-master' into 'master'

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