[gtk] (8 commits) Non-fast-forward update to branch gl-linear

[Matthias Clasen <matthiasc src gnome org>]

The branch 'gl-linear' 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:

  016b730... gl: Use GL_LINEAR for some offscreen rendering
  e490ac2... Update gsk tests

Commits added to the branch:

  1a8f109... Add a simple testcase for transforms (*)
  fd7a906... Cosmetic improvement to the layout manager demo (*)
  acc2516... Add another layout manager demo (*)
  9844014... Merge branch 'layout-manager-transform-demo' into 'master' (*)
  887539e... gridview: Make constructor arguments nullable (*)
  1a131a0... 3.99.1 (*)
  59a18ca... gl: Use GL_LINEAR for some offscreen rendering
  85efd4b... Update gsk tests

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