[gnome-control-center] (10 commits) Non-fast-forward update to branch wip/jsparber/background

[Julian Sparber <jsparber src gnome org>]

The branch 'wip/jsparber/background' 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:

  912531d... background: make cc_background_grid_item_set_ref static and
  9915b3b... background: cache tumbnail for wallpaper gallery for a redr
  bf54d57... background: changed variable names and small style changes
  b9f20fb... background: cache slideshow-emblem icon
  78c783a... background: show only top border for gallery view
  ede20ea... background: adapt meson.build for file changes
  d326949... background: change description for open in File and open in
  855f58f... background: fix crash of g-c-c by opening gnome-photos
  5023527... background: use autoptr where possible
  144a7ef... background: clean up files and code and remove build warnin

Commits added to the branch:

  4814bf1... background: refactor cc-background-grid-item
  4a2b006... background: cache tumbnail for wallpaper gallery for a redr
  aaad6fc... background: changed variable names and small style changes
  0f9a71c... background: cache slideshow-emblem icon
  7252625... background: show only top border for gallery view
  7739876... background: adapt meson.build for file changes
  75e6ca8... background: change description for open in File and open in
  402bac4... background: fix crash of g-c-c by opening gnome-photos
  1d71b9f... background: use autoptr where possible
  e11317a... background: clean up files and code and remove build warnin