Roll src/third_party/dawn cab352c2f679..73d5bb57e64f (3 commits)

This also updates the implementation of dawn_platform.h in Chromium
for tracing to match the new function signature in Dawn.

https://dawn.googlesource.com/dawn.git/+log/cab352c2f679..73d5bb57e64f

git log cab352c2f679..73d5bb57e64f --date=short --no-merges --format='%ad %ae %s'
2019-10-28 enga@chromium.org Use enums for trace event categories
2019-10-28 enga@chromium.org perf_tests: Always capture trace events and flush incrementally
2019-10-28 cwallez@chromium.org Make unittests and fuzzers use webgpu.h

Created with:
  gclient setdep -r src/third_party/dawn@73d5bb57e64f

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@chromium.org, kbr@chromium.org

Change-Id: I375a213338e12b4e15e6c49cbf399955fc1857bf
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1885451Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Austin Eng <enga@chromium.org>
Cr-Commit-Position: refs/heads/master@{#710168}

DEPS

@@ -307,7 +307,7 @@ 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': 'cab352c2f6793f22ff0ea6f2717ff9039cbfc0c4',
+  'dawn_revision': '73d5bb57e64faafd857b3d6d3c580e3f57a992d3',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.

gpu/command_buffer/service/dawn_platform.cc

@@ -15,8 +15,10 @@ DawnPlatform::DawnPlatform() = default;
 DawnPlatform::~DawnPlatform() = default;
 
 const unsigned char* DawnPlatform::GetTraceCategoryEnabledFlag(
-    const char* category_group) {
-  return TRACE_EVENT_API_GET_CATEGORY_GROUP_ENABLED(category_group);
+    dawn_platform::TraceCategory category) {
+  // For now, all Dawn trace categories are put under "gpu.dawn"
+  return TRACE_EVENT_API_GET_CATEGORY_GROUP_ENABLED(
+      TRACE_DISABLED_BY_DEFAULT("gpu.dawn"));
 }
 
 double DawnPlatform::MonotonicallyIncreasingTime() {

gpu/command_buffer/service/dawn_platform.h

@@ -16,7 +16,7 @@ class DawnPlatform : public dawn_platform::Platform {
   ~DawnPlatform() override;
 
   const unsigned char* GetTraceCategoryEnabledFlag(
-      const char* category_group) override;
+      dawn_platform::TraceCategory category) override;
 
   double MonotonicallyIncreasingTime() override;