Roll src/third_party/dawn c1583a558c58..54b4df706968 (4 commits)

https://dawn.googlesource.com/dawn.git/+log/c1583a558c58..54b4df706968

git log c1583a558c58..54b4df706968 --date=short --no-merges --format='%ad %ae %s'
2019-08-02 beaufort.francois@gmail.com s/isPIXEventRuntimeLoaded/IsPIXEventRuntimeLoaded/g
2019-08-02 cwallez@chromium.org Implement most texture formats on OpenGL
2019-08-02 beaufort.francois@gmail.com Handle debug markers commands for compute pass encoder
2019-08-02 beaufort.francois@gmail.com Make fragment stage optional in RenderPipeline

Created with:
  gclient setdep -r src/third_party/dawn@54b4df706968

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: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
TBR=cwallez@google.com

Bug: None
Change-Id: Ifa8fc0523cff41f59f34a6f0e0767c3b89ee019c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1733192Reviewed-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@{#683560}

DEPS

@@ -280,7 +280,7 @@ 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': 'c1583a558c5898098423bc2de0b9da1ab04f4770',
+  'dawn_revision': '54b4df706968359c8c5a332e06de3dc3d372e2c8',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.