[mutter] (6 commits) Non-fast-forward update to branch wip/carlosg/unassorted-perf-fixes

[Carlos Garnacho <carlosg src gnome org>]

The branch 'wip/carlosg/unassorted-perf-fixes' 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:

  6c9f7e1... clutter: Avoid rounding compensation when invalidating 2D a
  6ec6729... compositor: Avoid changing pipeline/source if shadow is not
  29a1288... cogl: Ensure to only clear the depth buffer if depth testin
  517ec28... Revert "Revert "ClutterActor: Optimize away idempotent scal

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