Better image for copyTo4444 test

This one produces noticeable differences if we fail to dither.

Bug:720105
Change-Id: I208d0c8147f4cca1b484f2f55edc09ce1bef2dcb
Reviewed-on: https://skia-review.googlesource.com/18036
Commit-Queue: Mike Klein <mtklein@chromium.org>
Reviewed-by: Mike Klein <mtklein@chromium.org>
1 file changed