Roll src/third_party/dawn c8eff1c1e1b8..b47470daa737 (2 commits)

https://dawn.googlesource.com/dawn.git/+log/c8eff1c1e1b8..b47470daa737


git log c8eff1c1e1b8..b47470daa737 --date=short --no-merges --format='%ad %ae %s'
2019-03-05 jiawei.shao@intel.com Return an error ComputePassEncoder when error occurs in BeginComputePass
2019-03-05 jiawei.shao@intel.com Fix crashes when using error textures in copy commands


Created with:
  gclient setdep -r src/third_party/dawn@b47470daa737

The AutoRoll server is located here: https://autoroll.skia.org/r/dawn-chromium-autoroll

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

If the roll is causing failures, please contact the current sheriff, who should
be CC'd on the roll, and stop the roller if necessary.

CQ_INCLUDE_TRYBOTS=luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel

BUG=chromium:937628
TBR=cwallez@chromium.org

Change-Id: Ic563a8dc8c7c0c633442618fb607ea30e0570e29
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1502592Reviewed-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@{#637631}

DEPS

@@ -254,7 +254,7 @@ 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': 'c8eff1c1e1b88b98b2cf1fa52efbac487f4a747c',
+  'dawn_revision': 'b47470daa7377a804df5d94e7a93b5925a57f84a',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.