[mutter] (8 commits) ...clutter/offscreen-effect: Remove clutter_offscreen_effect_get_target_rect

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

Summary of changes:

  67129c7... clutter/effect: Don't expose pre and post paint helpers (*)
  f5c77df... clutter/offscreen-effect: Unref framebuffer on pre_paint (*)
  de01dea... clutter/offscreen-effect: Simplify paint (*)
  f650004... clutter/paint-nodes: Don't skip pipeline node constructor (*)
  cef6534... clutter/offscreen-effect: Remove CoglMaterial from public A (*)
  4435bec... clutter/offscreen-effect: Undeprecate clutter_offscreen_eff (*)
  cce4d75... clutter/deform-effect: Use clutter_offscreen_effect_get_tar (*)
  c7ab5f3... clutter/offscreen-effect: Remove clutter_offscreen_effect_g (*)

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