[mutter] (2 commits) Non-fast-forward update to branch wip/smcv/shell2538-robustness

[Simon McVittie <smcv src gnome org>]

The branch 'wip/smcv/shell2538-robustness' 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:

  8e8544d... cogl: Don't allow creating sized textures with 0 pixels
  751487f... cogl: Defend against empty or unallocated framebuffers

Commits added to the branch:

  c6ec85b... cogl: Don't allow creating sized textures with 0 pixels
  553b944... cogl: Defend against empty or unallocated framebuffers