[mutter] (17 commits) Non-fast-forward update to branch wip/carlosg/sound-abstraction

[Carlos Garnacho <carlosg src gnome org>]

The branch 'wip/carlosg/sound-abstraction' 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:

  a6b677d... core: Add MetaSound abstraction
  c931693... core: Make MetaBell use MetaSound to play the bell sound
  de83131... workspace: Port to MetaSound
  28b9094... build: Make libcanberra no longer optional

Commits added to the branch:

  a7df459... clutter: Avoid rounding compensation when invalidating 2D a (*)
  3c6a518... compositor: Avoid changing pipeline/source if shadow is not (*)
  4139907... cogl: Ensure to only clear the depth buffer if depth testin (*)
  2e79d05... Revert "Revert "ClutterActor: Optimize away idempotent scal (*)
  697aeae... clutter/tests: Update expectations in actor-anchors test (*)
  1d73533... tests: Don't check pixels outside actor allocation (*)
  6502735... cogl: Remove mesa_46631_slow_read_pixels_workaround (*)
  981b045... cogl: Pick glReadPixels format by target, not source (*)
  05ab8ee... cogl/tests: Use tmp file to dump test results (*)
  dcb5253... build: Move libmutter_name to toplevel Meson file (*)
  ebb6c56... Add Meson support for installed tests (*)
  9bd427a... meta/tests: Remove commented lines (*)
  7a75692... meson: Print some configure flags (*)
  61bea75... core: Add MetaSound abstraction
  02b5404... core: Make MetaBell use MetaSound to play the bell sound
  f877708... workspace: Port to MetaSound
  22381d8... build: Make libcanberra no longer optional

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