Roll src/third_party/dawn 631f4258a1ac..f70786126c8b (1 commits)

https://dawn.googlesource.com/dawn.git/+log/631f4258a1ac..f70786126c8b

git log 631f4258a1ac..f70786126c8b --date=short --first-parent --format='%ad %ae %s'
2020-01-16 rharrison@chromium.org Rolling 4 dependencies for Vk1.2 support integration

Created with:
  gclient setdep -r src/third_party/dawn@f70786126c8b

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/dawn-chromium-autoroll
Please CC cwallez@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

Cq-Include-Trybots: luci.chromium.try:dawn-linux-x64-deps-rel;luci.chromium.try:dawn-mac-x64-deps-rel;luci.chromium.try:dawn-win10-x64-deps-rel;luci.chromium.try:dawn-win10-x86-deps-rel
Bug: None
Tbr: cwallez@google.com
Change-Id: I8c6631e74f135d53c66a8f97e8c417e7cd256d8f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2004371Reviewed-by: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Commit-Queue: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#732506}

DEPS

@@ -312,7 +312,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.
-  'dawn_revision': '631f4258a1ace016d6a10ebf7ff127ea46be8575',
+  'dawn_revision': 'f70786126c8b8c84af8dbf828b98567a8101c9c2',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.