A stray iostream got introduced in
28b6528c

BUG=angleproject:1522

Change-Id: Ib0b14b47d4786309ec2d39acb5531f3772b91f20
Reviewed-on: https://chromium-review.googlesource.com/386256Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>