[mutter] (18 commits) Non-fast-forward update to branch wip/nielsdg/remove-gl-alpha

[Niels De Graef <nielsdg src gnome org>]

The branch 'wip/nielsdg/remove-gl-alpha' 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:

  1a60067... cogl: Don't Use GL_ALPHA

Commits added to the branch:

  912a9ec... clutter/stage-cogl: Use G_USEC_PER_SEC instead of hardcoded (*)
  ccf27e5... clutter/stage-cogl: Schedule immediate update on zero refre (*)
  a76762a... clutter/stage-cogl: Use default frame rate instead of hardc (*)
  35aa278... clutter/stage-cogl: Stop `schedule_update` repeatedly retur (*)
  67a3715... clutter/stage-cogl: Reduce while loop iterations (*)
  e415cc5... clutter/master-clock: Remove fallback throttles (*)
  1dbf25a... clutter/stage-cogl: Protect against extremely high refresh  (*)
  9b53583... cogl/trace: Fix typo (*)
  5eac1d6... wayland/surface: Clear texture when attaching NULL (*)
  36b3616... wayland/cursor-surface: Update sprite when attaching NULL (*)
  e48c7c0... clutter/stage: Make view fetch helper take floats (*)
  4abca41... clutter/stage: Expose stage view getter helper as API (*)
  178b975... cursor-renderer: Align OpenGL cursor rect to physical pixel (*)
  c237bc5... clutter-effect: Rename get_paint_volume (*)
  9db9793... clutter: Clarify clutter_stage_get_actor_at_pos docs (*)
  c24d8e8... clutter/x11: Fix build without libwacom (*)
  d3e789e... Updated Spanish translation (*)
  07fde87... cogl: Don't use GL_ALPHA

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