GM self-test: add option to exercise --writePath and --mismatchPath, but not on bots
(individual developers can set WRITE_IMAGE_FILES=1 for local testing)

R=rmistry@google.com

Review URL: https://codereview.chromium.org/14863009

git-svn-id: http://skia.googlecode.com/svn/trunk@9056 2bbb7eff-a529-9590-31e7-b0007b416f81
1 file changed