Mark fast/images/image-zoom-to-25.html as needing rebaseline

TBR=ojan@chromium.org
BUG=

Review URL: https://codereview.chromium.org/268673023

git-svn-id: svn://svn.chromium.org/blink/trunk@173435 bbb929c8-8fbe-4397-9dbb-9b2b20218538