Add buggy GPU baselines for MultiPictureDraw Sierpinski GM (with bug label)

I am checking in these baseline images even though they are afflicted by a bug (skia:2979).

NOTRY=true
NOTREECHECKS=true
BUG=skia:2979
TBR=jvanverth@google.com

Review URL: https://codereview.chromium.org/619873003
35 files changed