[librsvg] (6 commits) Non-fast-forward update to branch alatiera/pixbuf-utils-comp

[Federico Mena Quintero <federico src gnome org>]

The branch 'alatiera/pixbuf-utils-comp' 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:

  8e136c0... Update compiling docs for debian
  a47cb7d... Update COMPILING.md

Commits added to the branch:

  c05fd57... DrawingCtx: remove the surfaces_stack (*)
  85ffed8... compute_effects_region(): Make into a method of NodeFilter (*)
  d594bf9... feImage: Pass the bounding boxes to render_external_image() (*)
  3204513... Update Cargo.lock; this just adds an auto-generated comment (*)
  0909948... Update compiling docs for debian
  8a0a8fe... Update COMPILING.md

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