This is bloating the WinRT binaries unnecessarily.

BUG=angleproject:1250

Change-Id: I87fa2422e7d58374329956540d03933b0177234b
Reviewed-on: https://chromium-review.googlesource.com/316820Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Tested-by: Geoff Lang <geofflang@chromium.org>