The tests that are prone to failing based on last few failures:
WebglConformance_deqp_functional_gles3_texturespecification_texstorage2d_format_2d_02
WebglConformance_deqp_functional_gles3_framebufferblit_default_framebuffer_05
WebglConformance_deqp_functional_gles3_fborender_resize_03

Failing builds:
https://build.chromium.org/p/chromium.gpu.fyi/builders/Mac%20GPU%20ASAN%20Release/builds/1184
https://build.chromium.org/p/chromium.gpu.fyi/builders/Mac%20GPU%20ASAN%20Release/builds/1173
https://build.chromium.org/p/chromium.gpu.fyi/builders/Mac%20GPU%20ASAN%20Release/builds/1170
https://build.chromium.org/p/chromium.gpu.fyi/builders/Mac%20GPU%20ASAN%20Release/builds/1169
https://build.chromium.org/p/chromium.gpu.fyi/builders/Mac%20GPU%20ASAN%20Release/builds/1168

Swarming logs:
https://chromium-swarm.appspot.com/task?id=3389b6ea5c835c10&refresh=10&show_raw=1
https://chromium-swarm.appspot.com/task?id=3384f4c2d96c5110&refresh=10&show_raw=1

Looks like a v8 bug:

#
# Fatal error in ../../v8/src/heap/spaces.h, line 2476
# Check failed: allocated <= Size() (16507312 vs. 16498608).
#

==== C stack trace ===============================

0 Chromium Framework 0x00000001167be583 v8::base::debug::StackTrace::StackTrace() + 19
1 Chromium Framework 0x00000001167b8c57 V8_Fatal + 423
2 Chromium Framework 0x000000010d6a1102 v8::internal::NewSpace::AllocatedSinceLastGC() + 1570
3 Chromium Framework 0x000000010d6974cd v8::internal::GCTracer::Start(v8::internal::GarbageCollector, v8::internal::GarbageCollectionReason, char const*) + 765
4 Chromium Framework 0x000000010d6b0594 v8::internal::Heap::CollectGarbage(v8::internal::GarbageCollector, v8::internal::GarbageCollectionReason, char const*, v8::GCCallbackFlags) + 1620
5 Chromium Framework 0x000000010d5e0e26 v8::internal::Factory::NewFillerObject(int, bool, v8::internal::AllocationSpace) + 310
6 Chromium Framework 0x000000010dece860 v8::internal::__RT_impl_Runtime_AllocateInNewSpace(v8::internal::Arguments, v8::internal::Isolate*) + 384
7 Chromium Framework 0x000000010decdea9 v8::internal::Runtime_AllocateInNewSpace(int, v8::internal::Object**, v8::internal::Isolate*) + 729
8 ??? 0x0000000130c0426e 0x0 + 5112873582
Received signal 4 <unknown> 0001167bc6fc
[0x000111d6f726]
[0x7fff905dd52a]
[0x000000000000]
[0x0001167b8c8f]
[0x00010d6a1102]
[0x00010d6974cd]
[0x00010d6b0594]
[0x00010d5e0e26]
[0x00010dece860]
[0x00010decdea9]
[0x000130c0426e]
[end of stack trace]