Pick up a version of GN which works around crbug.com/791295.
Now we get VS projects that don't hit the ninja bug described there.

BUG=angleproject:1569

Change-Id: I8758c63459640314a4c76b0d590d388c37ab3125
Reviewed-on: https://chromium-review.googlesource.com/1175035Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Frank Henigman <fjhenigman@chromium.org>