Got this here:
https://ci.chromium.org/buildbot/tryserver.chromium.win/win_optional_gpu_tests_rel/23408
and here:
https://ci.chromium.org/buildbot/chromium.gpu.fyi/Win10%20FYI%20Release%20%28NVIDIA%29/714
both times during WebglConformance_conformance_ogles_GL_cross_cross_001_to_002, but not certain if the particular test is responsible.

#
# Fatal error in ../../v8/src/heap/heap.cc, line 2252
# Check failed: memory_allocator()->IsMemoryChunkExecutable(*chunk).
#
#
#
#FailureMessage Object: 04BCBD10Backtrace:
	base::debug::StackTrace::StackTrace [0x698855C0+32]
	base::debug::StackTrace::StackTrace [0x69873FED+13]
	gin::V8Platform::GetStackTracePrinter [0x6A987F6F+39]
	V8_Fatal [0x6A97B1E7+183]
	v8::internal::Heap::ProtectUnprotectedMemoryChunks [0x6913304D+445]
	v8::internal::Factory::NewCode [0x69113B5E+974]
	v8::internal::compiler::CodeGenerator::FinalizeCode [0x68EB7009+217]
	v8::internal::compiler::PipelineImpl::Run<v8::internal::compiler::FinalizeCodePhase> [0x68FB719D+77]
	v8::internal::compiler::PipelineImpl::FinalizeCode [0x68FB2DD9+41]
	v8::internal::compiler::PipelineCompilationJob::FinalizeJobImpl [0x68FB2D14+36]
	v8::internal::OptimizedCompilationJob::FinalizeJob [0x68E8183C+156]
	v8::internal::Compiler::Compile [0x68E83586+3222]
	v8::internal::Compiler::CompileOptimized [0x68E83FEC+92]
	v8::internal::Runtime_CompileOptimized_NotConcurrent [0x69393AC2+866]
	v8::internal::Runtime_CompileOptimized_NotConcurrent [0x69393827+199]
Received fatal exception EXCEPTION_ACCESS_VIOLATION
Backtrace:
	base::win::SetAbortBehaviorForCrashReporting [0x697FDC90+32]
	v8::base::OS::Abort [0x6A97D6F0+48]
	V8_Fatal [0x6A97B1FF+207]
	v8::internal::Heap::ProtectUnprotectedMemoryChunks [0x6913304D+445]
	v8::internal::Factory::NewCode [0x69113B5E+974]
	v8::internal::compiler::CodeGenerator::FinalizeCode [0x68EB7009+217]
	v8::internal::compiler::PipelineImpl::Run<v8::internal::compiler::FinalizeCodePhase> [0x68FB719D+77]
	v8::internal::compiler::PipelineImpl::FinalizeCode [0x68FB2DD9+41]
	v8::internal::compiler::PipelineCompilationJob::FinalizeJobImpl [0x68FB2D14+36]
	v8::internal::OptimizedCompilationJob::FinalizeJob [0x68E8183C+156]
	v8::internal::Compiler::Compile [0x68E83586+3222]
	v8::internal::Compiler::CompileOptimized [0x68E83FEC+92]
	v8::internal::Runtime_CompileOptimized_NotConcurrent [0x69393AC2+866]
	v8::internal::Runtime_CompileOptimized_NotConcurrent [0x69393827+199]
	(No symbol) [0x3E406CCA]
	(No symbol) [0x3E419015]
	(No symbol) [0x3E419244]
	(No symbol) [0x3E419244]
	(No symbol) [0x3E419244]
	(No symbol) [0x3E419244]
	(No symbol) [0x3E419244]
	(No symbol) [0x3E40FD3D]
	(No symbol) [0x3E414BDC]
	(No symbol) [0x3E407D71]
	v8::internal::Execution::New [0x690D52AE+894]
	v8::internal::Execution::Call [0x690D4E07+247]
	v8::internal::Execution::Call [0x690D4D31+33]
	v8::Function::Call [0x68D719E3+563]
	blink::V8ScriptRunner::CallFunction [0x6B713B4D+577]
	blink::V8EventListener::CallListenerFunction [0x6B77538B+371]
	blink::V8AbstractEventListener::InvokeEventHandler [0x6B7321E5+307]
	blink::V8AbstractEventListener::HandleEvent [0x6B732051+179]
	blink::V8AbstractEventListener::handleEvent [0x6B731F7C+188]
	blink::EventTarget::FireEventListeners [0x6A995971+1063]
	blink::EventTarget::FireEventListeners [0x6A99538C+418]
	blink::EventTarget::DispatchEventInternal [0x6A9951DD+43]
	blink::XMLHttpRequestProgressEventThrottle::DispatchReadyStateChangeEvent [0x6AF7B7DB+155]
	blink::XMLHttpRequest::DispatchReadyStateChangeEvent [0x6AF75A1B+165]
	blink::XMLHttpRequest::EndLoading [0x6AF798BF+127]
	blink::XMLHttpRequest::DidFinishLoadingInternal [0x6AF7982B+215]
	blink::XMLHttpRequest::DidFinishLoading [0x6AF796D8+296]
	blink::DocumentThreadableLoader::HandleSuccessfulFinish [0x6BC7CC70+156]
	blink::DocumentThreadableLoader::NotifyFinished [0x6BC7BB41+283]
	blink::Resource::NotifyFinished [0x69634A4A+150]
	blink::Resource::Finish [0x69635577+151]
	blink::ResourceFetcher::HandleLoaderFinish [0x6964181E+952]
	blink::ResourceLoader::DidFinishLoading [0x6964FCAA+224]
	content::WebURLLoaderImpl::Context::OnCompletedRequest [0x6B11914E+338]
	content::ResourceDispatcher::OnRequestComplete [0x6B130DC7+915]
	content::URLResponseBodyConsumer::NotifyCompletionIfAppropriate [0x6B2208BF+63]
	content::URLResponseBodyConsumer::OnComplete [0x6B220879+93]
	content::ThrottlingURLLoader::OnComplete [0x68A5C5E9+169]
	network::mojom::URLLoaderClientStubDispatch::Accept [0x68538FDA+1166]
	network::mojom::URLLoaderClientStub<mojo::RawPtrImplRefTraits<network::mojom::URLLoaderClient> >::Accept [0x685221BD+19]
	mojo::InterfaceEndpointClient::HandleValidatedMessage [0x698C9D0D+541]
	mojo::FilterChain::Accept [0x698CD697+131]
	mojo::InterfaceEndpointClient::HandleIncomingMessage [0x698CABA6+106]
	mojo::internal::MultiplexRouter::ProcessIncomingMessage [0x698C4A56+698]
	mojo::internal::MultiplexRouter::Accept [0x698C45DD+295]
	mojo::FilterChain::Accept [0x698CD697+131]
	mojo::Connector::ReadSingleMessage [0x698C7F76+364]
	mojo::Connector::ReadAllAvailableMessages [0x698C863F+87]
Found crashpad_database_util
Minidump found: c:\b\s\w\itc_gpgc\tmpisnf3m\reports\4ded8014-049c-46ba-a99b-0075eed92f48.dmp
Uploading c:\b\s\w\itc_gpgc\tmpisnf3m\reports\4ded8014-049c-46ba-a99b-0075eed92f48.dmp to gs://chrome-telemetry-output/minidump-2018-04-10_05-00-47-158202.dmp