This is flaky on almost all bots:
https://build.chromium.org/p/chromium.gpu.fyi/builders/Win7%20x64%20Release%20%28NVIDIA%29/builds/8307
https://build.chromium.org/p/chromium.gpu.fyi/builders/Mac%2010.10%20Retina%20Release%20%28AMD%29/builds/11197
https://build.chromium.org/p/chromium.gpu.fyi/builders/Linux%20Release%20%28NVIDIA%29/builds/45609
https://build.chromium.org/p/chromium.gpu.fyi/builders/Linux%20Release%20%28New%20Intel%29/builds/3453

Yes, been seeing this a lot as well on the angle try waterfall. Probably just needs a flaky suppression for now. Stephen can you add a flaky suppression to the WebGL 2 test expectations as part of your pixel wrangling?

Although it is weird that it happens across platforms on different GPUs.. that makes me wonder if it's a bug in the test.

Actually, maybe it's a bug in v8?

#0 0x7f18a16d184e base::debug::StackTrace::StackTrace()
#1 0x7f18a16eb19b logging::LogMessage::~LogMessage()
#2 0x7f18a39c8fb1 blink::ScriptWrappableVisitorVerifier::pushToMarkingDeque()
#3 0x7f18a4c0794b blink::WebGLFramebuffer::traceWrappers()
#4 0x7f18a39c7673 blink::ScriptWrappableVisitor::TraceEpilogue()
#5 0x7f18a0331450 v8::internal::MarkCompactCollector::MarkLiveObjects()
#6 0x7f18a03305d2 v8::internal::MarkCompactCollector::CollectGarbage()
#7 0x7f18a030e473 v8::internal::Heap::MarkCompact()
#8 0x7f18a030cad8 v8::internal::Heap::PerformGarbageCollection()
#9 0x7f18a030bc81 v8::internal::Heap::CollectGarbage()
#10 0x7f18a030a7c1 v8::internal::Heap::HandleGCRequest()
#11 0x7f18a02c89db v8::internal::StackGuard::HandleInterrupts()
#12 0x7f18a0585757 v8::internal::Runtime_Interrupt()
#13 0x22b34af0426e <unknown>

Adding V8 label to get help from someone on the team.

I logged this as  crbug.com/671791 , which Ken then duped into  crbug.com/671942  (although it referred to a different test).

Folks on the V8 team then fixed and closed the latter. So either this test is still flaky, or the V8 fix didn't work.