Add svg/animations/repeatn-event-1c.svg to TestExpectations in debug.

Gardening.

BUG=352377
TBR=zmo@chromium.org
TEST=debug bots

Review URL: https://codereview.chromium.org/196473017

git-svn-id: svn://svn.chromium.org/blink/trunk@169170 bbb929c8-8fbe-4397-9dbb-9b2b20218538