Switch Windows to build with in-tree libc++

Design document:
https://docs.google.com/document/d/1VPxepzuyWbXFzv1VpkSKEn0wPvSUffpcaOLislhcwrA/edit?usp=sharing

chromium-dev@ announcement:
https://groups.google.com/a/chromium.org/forum/#!topic/chromium-dev/LqlnZ8sWcME

BUG=801780
R=thakis

Change-Id: Id60ba267d533b3c54ecc5d72852f7a16220fe244
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1465168
Commit-Queue: Thomas Anderson <thomasanderson@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#641450}
1 file changed