[gtk] (3 commits) Non-fast-forward update to branch heif-demo

[Matthias Clasen <matthiasc src gnome org>]

The branch 'heif-demo' 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:

  e51dc6b... Add gdk_color_profile_new_from_cicp
  b4d535f... Add a quick-and-dirty heif loading test
  d84a297... widget-factory: Add an hdr image example

Commits added to the branch:

  fb2765c... Add gdk_color_profile_new_from_cicp
  d527f9b... Add a quick-and-dirty heif loading test
  73ba1da... widget-factory: Add an hdr image example