This should also fix the VS project generation. Thanks to Jeff Gilbert
from Mozilla for sharing a list of missing files.

Bug: angleproject:2360
Change-Id: Ideab28a0169cd7aabb6a7bd3aac3a5832443f023
Reviewed-on: https://chromium-review.googlesource.com/922874Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>