Roll Dawn from 875091308b04 to aff4c0366314 (8 revisions)

https://dawn.googlesource.com/dawn.git/+log/875091308b04..aff4c0366314

2020-10-19 enga@chromium.org Fix unused variable warnings on ChromeOS
2020-10-19 dawn-autoroll@skia-public.iam.gserviceaccount.com Roll Tint from c9a3e4739678 to 7156d3e3140b (1 revision)
2020-10-19 dawn-autoroll@skia-public.iam.gserviceaccount.com Roll Tint from 89042538376b to c9a3e4739678 (1 revision)
2020-10-19 enga@chromium.org Add missing include in SwapChainVk
2020-10-19 dsinclair@chromium.org Fixup cmake file
2020-10-19 enga@chromium.org Reland "Replace the wire serializer with a no-op impl on disconnect"
2020-10-19 jiawei.shao@intel.com Add the entry point of CreateReadyComputePipeline
2020-10-17 cwallez@chromium.org Initial new swapchains on Vulkan.

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 dsinclair@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/+doc/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: chromium:951558
Tbr: dsinclair@google.com
Change-Id: Ib016997050dc5ce881fc8bd21de57971687bec0e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2485598Reviewed-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@{#818566}

DEPS

@@ -329,7 +329,7 @@ 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': '875091308b04ba87e29c929ed707f27889c660ea',
+  'dawn_revision': 'aff4c0366314c445dda2537a2f27c8c60ddf51da',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.