The test just prints the source text of each line on the stack.
Look how beautiful it reads \o/

BUG=chromium:659715
R=yangguo@chromium.org, kozyatinskiy@chromium.org
CC=titzer@chromium.org

Review-Url: https://codereview.chromium.org/2492123003
Cr-Commit-Position: refs/heads/master@{#41068}