Fix a -Wextra warning in branded builds.
Fix a -Wextra warning in branded builds.

BUG=567877
TBR=gab@chromium.org

Review URL: https://codereview.chromium.org/1521183002 .

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#364861}

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