[gtk+] (3 commits) Non-fast-forward update to branch wip/gbsneto/css-blend-modes

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

The branch 'wip/gbsneto/css-blend-modes' 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:

  5f224d8... css: add background-blend-mode support
  65dcdc0... css: add documentation for background-blend-mode
  e8771de... demo: add a demo for blend modes

Commits added to the branch:

  507d45c... css: add background-blend-mode support
  8994607... css: add documentation for background-blend-mode
  3478415... demo: add a demo for blend modes