[gtk] (4 commits) Non-fast-forward update to branch places-sidebar-dnd

[Ernestas Kulik <ernestask src gnome org>]

The branch 'places-sidebar-dnd' 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:

  e725984... placessidebar: Take a GdkDrag in _set_drop_targets_visible(

Commits added to the branch:

  05ca6bc... gl: fix compilation errors for legacy context shaders (*)
  19873e5... gl: implement clipping for legacy contexts (*)
  9dc6793... Merge branch 'legacy-gl' into 'master' (*)
  d05ccb6... placessidebar: Take a GdkDrag in _set_drop_targets_visible(

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