Fix clang/win build after https://codereview.chromium.org/1685053002

It complains about unused stuff on Windows.

BUG=82385
R=khushalsagar@chromium.org
TBR=khushalsagar@chromium.org

Review URL: https://codereview.chromium.org/1774713002 .

Cr-Commit-Position: refs/heads/master@{#379678}
1 file changed