Fix iOS after https://codereview.chromium.org/1278433002/
Fix iOS after https://codereview.chromium.org/1278433002/

Inadvertently removed lines from ios_chrome.gyp due to a bad rebase.

Review URL: https://codereview.chromium.org/1274213004

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#342361}

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