Rebaseline compositing/repaint tests post r172172.

TBR=aboxhall@chromium.org
BUG=

Review URL: https://codereview.chromium.org/248543002

git-svn-id: svn://svn.chromium.org/blink/trunk@172297 bbb929c8-8fbe-4397-9dbb-9b2b20218538