Unbreak win gn build.
Unbreak win gn build.

Apparently the gn win bot isn't set up in a way where it can detect
build failures reliably :-/

BUG=527453
TBR=brettw

Review URL: https://codereview.chromium.org/1323953004

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#346951}

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