Fix one last warning now that -Wall and -Werror is turned on for the testing directory as well for android.

BUG=312287
NOTRY=true
R=thakis@chromium.org

Review URL: https://codereview.chromium.org/58893003

Patch from Laszlo Gombos <l.gombos@samsung.com>>.

git-svn-id: svn://svn.chromium.org/blink/trunk@161305 bbb929c8-8fbe-4397-9dbb-9b2b20218538