Only a bug sighting; not sure whether this is reproducible.

In https://build.chromium.org/p/tryserver.chromium.win/builders/win_optional_gpu_tests_rel/builds/3942 , WebglConformance_conformance2_textures_video_tex_2d_rgba32f_rgba_float failed in the following way. Not sure whether this is related to other failures to load the actual video being tracked in other bugs (not in front of me right now).

WebglConformance_conformance2_textures_video_tex_2d_rgba32f_rgba_float (gpu_tests.webgl_conformance_integration_test.WebGLConformanceIntegrationTest) ... [3232:872:0922/120525:ERROR:interface_registry.cc(99)] Failed to locate a binder for interface: dom_distiller::mojom::DistillabilityService
[3232:12:0922/120525:ERROR:audio_manager_win.cc(464)] GetPreferredAudioParameters failed: 88890004
[3232:872:0922/120525:ERROR:interface_registry.cc(99)] Failed to locate a binder for interface: dom_distiller::mojom::DistillabilityService
[1628:3956:0922/120525:INFO:gpu_video_decode_accelerator_factory.cc(163)] Initializing DXVA HW decoder for windows.
[3232:12:0922/120525:ERROR:audio_manager_win.cc(464)] GetPreferredAudioParameters failed: 88890004
[3232:12:0922/120525:ERROR:audio_output_resampler.cc(295)] Unable to open audio device in low latency mode.  Falling back to high latency audio output.
[3232:12:0922/120525:ERROR:audio_output_resampler.cc(305)] Unable to open audio device in high latency mode.  Falling back to fake audio output.
[1628:3956:0922/120525:ERROR:dxva_video_decode_accelerator_win.cc(345)] The eglQueryDeviceAttribEXT function failed to get the device
[1628:3956:0922/120525:ERROR:mf_helpers.cc(12)] Error in dxva_video_decode_accelerator_win.cc on line 345
[3232:3244:0922/120526:ERROR:ssl_client_socket_impl.cc(1145)] handshake failed; returned -1, SSL error code 1, net_error -100
ASSERTION FAILED: !m_heapDoesNotContainCache->lookup(address)
e:\b\c\b\win\src\third_party\webkit\source\platform\heap\heap.cpp(338) : unsigned char *__thiscall blink::ThreadHeap::checkAndMarkPointer(class blink::Visitor *,unsigned char *)
Backtrace:
	blink::ThreadHeap::checkAndMarkPointer [0x6897A3CD+223]
	blink::ThreadState::visitStack [0x68988165+70]
	blink::ThreadHeap::visitStackRoots [0x6897C2B0+195]
	blink::ThreadState::collectGarbage [0x6898339F+463]
	blink::ThreadState::scheduleGCIfNeeded [0x689861DF+159]
	blink::NormalPageArena::outOfLineAllocate [0x6897EF8C+206]
	blink::NormalPageArena::allocateObject [0x6897D3B5+221]
	blink::ThreadHeap::allocateOnArenaIndex [0x689C69DD+127]
	blink::ThreadHeap::allocate<blink::Resource> [0x697CE1D4+54]
	blink::Resource::operator new [0x697CE2AD+14]
	blink::RawResource::RawResourceFactory::create [0x6A63372D+16]
	blink::ResourceFetcher::createResourceForLoading [0x697BEFC3+273]
	blink::ResourceFetcher::requestResource [0x697C362D+1235]
	blink::RawResource::fetchMedia [0x6A633F1A+200]
	blink::DocumentThreadableLoader::loadRequest [0x69A713D2+698]
	blink::DocumentThreadableLoader::dispatchInitialRequest [0x69A7075E+67]
	blink::DocumentThreadableLoader::start [0x69A72EDA+1133]
	blink::AssociatedURLLoader::loadAsynchronously [0x69449B64+862]
	media::ResourceMultiBufferDataProvider::Start [0x69FF5A03+869]
	media::ResourceMultiBuffer::CreateWriter [0x69FE95A7+49]
	media::MultiBuffer::AddReader [0x69FF338C+439]
	media::MultiBufferReader::UpdateInternalState [0x6A000E61+541]
	media::MultiBufferReader::SetPreload [0x6A0009E1+136]
	media::MultibufferDataSource::UpdateBufferSizes [0x69FFC0AA+482]
	media::MultibufferDataSource::CreateResourceLoader [0x69FFAB45+212]
	media::MultibufferDataSource::Initialize [0x69FFAD30+247]
	media::WebMediaPlayerImpl::DoLoad [0x69FEC91B+851]
	base::internal::FunctorTraits<void (__thiscall media::WebMediaPlayerImpl::*)(enum blink::WebMediaPlayer::LoadType,blink::WebURL const &,enum blink::WebMediaPlayer::CORSMode),void>::Invoke<base::WeakPtr<media::WebMediaPlayerImpl> const &,enum blink::WebMed [0x69FEB6D2+32]
	base::internal::InvokeHelper<1,void>::MakeItSo<void (__thiscall media::WebMediaPlayerImpl::*const &)(enum blink::WebMediaPlayer::LoadType,blink::WebURL const &,enum blink::WebMediaPlayer::CORSMode),base::WeakPtr<media::WebMediaPlayerImpl> const &,enum bli [0x69FEB794+40]
	base::internal::Invoker<base::internal::BindState<void (__thiscall media::WebMediaPlayerImpl::*)(enum blink::WebMediaPlayer::LoadType,blink::WebURL const &,enum blink::WebMediaPlayer::CORSMode),base::WeakPtr<media::WebMediaPlayerImpl>,enum blink::WebMedia [0x69FEB822+27]
	base::internal::Invoker<base::internal::BindState<void (__thiscall media::WebMediaPlayerImpl::*)(enum blink::WebMediaPlayer::LoadType,blink::WebURL const &,enum blink::WebMediaPlayer::CORSMode),base::WeakPtr<media::WebMediaPlayerImpl>,enum blink::WebMedia [0x69FEE87C+22]
	ChromeContentRendererClient::DeferMediaLoad [0x69E5FCCF+122]
	base::internal::Invoker<base::internal::BindState<void (__thiscall content::ContentRendererClient::*)(content::RenderFrame *,bool,base::Callback<void __cdecl(void),1,1> const &),base::internal::UnretainedWrapper<content::ContentRendererClient>,content::Re [0x69EC2B6A+23]
	media::WebMediaPlayerImpl::load [0x69FF0108+477]
	blink::HTMLMediaElement::startPlayerLoad [0x6986F7AE+918]
	blink::HTMLMediaElement::loadResource [0x6986937C+1213]
	blink::HTMLMediaElement::loadSourceFromAttribute [0x6986946C+163]
	blink::HTMLMediaElement::selectMediaResource [0x6986C9FB+414]
	blink::HTMLMediaElement::loadInternal [0x69868DFC+247]
	blink::HTMLMediaElement::loadTimerFired [0x6986962B+49]
	blink::TaskRunnerTimer<blink::HTMLMediaElement>::fired [0x69867555+28]
	blink::TimerBase::runInternal [0x693F0BF5+419]
	??$MakeItSo@ABQ8WebMediaPlayerMSCompositor@content@@AEXXZABV?$WeakPtr@VWebMediaPlayerMSCompositor@content@@@base@@$$V@?$InvokeHelper@$00X@internal@base@@SAXABQ8WebMediaPlayerMSCompositor@content@@AEXXZABV?$WeakPtr@VWebMediaPlayerMSCompositor@content@@@2@@ [0x68094027+33]
	base::internal::Invoker<base::internal::BindState<void (__thiscall content::WebMediaPlayerMSCompositor::*)(void),base::WeakPtr<content::WebMediaPlayerMSCompositor> >,void __cdecl(void)>::Run [0x68095CA2+19]
	base::debug::TaskAnnotator::RunTask[3232:3244:0922/120527:ERROR:ssl_client_socket_impl.cc(1145)] handshake failed; returned -1, SSL error code 1, net_error -100
 [0x68AFA58B+267]
	blink::scheduler::TaskQueueManager::ProcessTaskFromWorkQueue [0x693EB5A0+594]
	blink::scheduler::TaskQueueManager::DoWork [0x693EAB6B+452]
	base::internal::FunctorTraits<void (__thiscall blink::scheduler::TaskQueueManager::*)(base::TimeTicks,bool),void>::Invoke<base::WeakPtr<blink::scheduler::TaskQueueManager> const &,base::TimeTicks const &,bool const &> [0x693E9E9F+34]
	base::internal::InvokeHelper<1,void>::MakeItSo<void (__thiscall blink::scheduler::TaskQueueManager::*const &)(base::TimeTicks,bool),base::WeakPtr<blink::scheduler::TaskQueueManager> const &,base::TimeTicks const &,bool const &> [0x693E9EC6+37]
	base::internal::Invoker<base::internal::BindState<void (__thiscall blink::scheduler::TaskQueueManager::*)(base::TimeTicks,bool),base::WeakPtr<blink::scheduler::TaskQueueManager>,base::TimeTicks,bool>,void __cdecl(void)>::RunImpl<void (__thiscall blink::sc [0x693E9EE2+23]
	base::internal::Invoker<base::internal::BindState<void (__thiscall blink::scheduler::TaskQueueManager::*)(base::TimeTicks,bool),base::WeakPtr<blink::scheduler::TaskQueueManager>,base::TimeTicks,bool>,void __cdecl(void)>::Run [0x693EB85C+22]
	base::debug::TaskAnnotator::RunTask [0x68AFA58B+267]
	base::MessageLoop::RunTask [0x68AA79A3+1203]
	base::MessageLoop::DoWork [0x68AA6D15+597]
	base::MessagePumpDefault::Run [0x68AFCED0+416]
	base::MessageLoop::RunHandler [0x68AA74E7+103]
	base::RunLoop::Run [0x68AE1FF9+41]
	content::RendererMain [0x69ED67EA+486]
	content::RunNamedProcessTypeMain [0x68A892CC+176]
	content::ContentMainRunnerImpl::Run [0x68A891EB+274]
	content::ContentMain [0x68A885C8+35]
	ChromeMain [0x67FBC7FE+158]