WebRtcGetUserMediaBrowserTest.VideoInIFrameAndCloseInSuccessCb is flaky on the tryserver win7_chromium_rel_ng, causing content_browsertests to fail and valid CQ jobs to be retried. There may be up to 15 instances of this failure in the last 200 builds:

https://luci-milo.appspot.com/buildbot/tryserver.chromium.win/win7_chromium_rel_ng/?limit=200

A few examples:

https://luci-milo.appspot.com/buildbot/tryserver.chromium.win/win7_chromium_rel_ng/8202
https://luci-milo.appspot.com/buildbot/tryserver.chromium.win/win7_chromium_rel_ng/8197
https://luci-milo.appspot.com/buildbot/tryserver.chromium.win/win7_chromium_rel_ng/8171
https://luci-milo.appspot.com/buildbot/tryserver.chromium.win/win7_chromium_rel_ng/8169
https://luci-milo.appspot.com/buildbot/tryserver.chromium.win/win7_chromium_rel_ng/8168

I see Issue 727601 was filed about the related tests:
WebRtcGetUserMedia{OldConstraints,}BrowserTest::AudioInIFrameAndCloseInSuccessCb

but that bug was filed in May and there's been no action on it except to disable tests.

This is affecting the CQ so I'm marking it P1. Here's the log excerpt of one of the failures. Note that per:
https://luci-logdog.appspot.com/v/?s=chromium%2Fbb%2Ftryserver.chromium.win%2Fwin7_chromium_rel_ng%2F8202%2F%2B%2Frecipes%2Fsteps%2Fcontent_browsertests__with_patch_%2F0%2Flogs%2FWebRtcGetUserMediaBrowserTest.VideoInIFrameAndCloseInSuccessCb%2F0

once this test fails, the 3 implicit retries all fail.

[4996:688:0930/114505.810:19437568:FATAL:media_stream_video_source.cc(257)] Check failed: STARTING == state_ (1 vs. 6)
Backtrace:
	base::debug::StackTrace::StackTrace [0x0239A1B7+55]
	base::debug::StackTrace::StackTrace [0x023B479A+10]
	content::MediaStreamVideoSource::OnStartDone [0x039E0FB6+277]
	content::MediaStreamVideoCapturerSource::OnRunStateChanged [0x03A03BC1+369]
	base::internal::Invoker<base::internal::BindState<void (__thiscall content::MediaStreamVideoCapturerSource::*)(media::VideoCaptureParams const &,bool),base::internal::UnretainedWrapper<content::MediaStreamVideoCapturerSource>,media::VideoCaptureParams>,vo [0x03A03F1F+31]
	content::MediaStreamVideoCapturerSource::OnRunStateChanged [0x03A03C86+566]
	??$DispatchToMethodImpl@PAVPPB_ImageData_Proxy@proxy@ppapi@@P8123@AEXHHABUPP_Size@@W4PP_Bool@@PAVHostResource@3@PAUPP_ImageDataDesc@@PAVSharedMemoryHandle@base@@@ZV?$tuple@HHUPP_Size@@W4PP_Bool@@@std@@V?$tuple@VHostResource@ppapi@@UPP_ImageDataDesc@@VShar [0x022CF954+169]
	content::MediaStreamVideoCapturerSource::RestartSourceImpl [0x03A03EED+381]
	base::RepeatingCallback<void __cdecl(bool)>::Run [0x010FB716+24]
	base::internal::FunctorTraits<base::RepeatingCallback<void __cdecl(enum blink::mojom::WebBluetoothResult)>,void>::Invoke<base::RepeatingCallback<void __cdecl(enum blink::mojom::WebBluetoothResult)>,enum blink::mojom::WebBluetoothResult> [0x016196B2+91]
	base::internal::Invoker<base::internal::BindState<base::RepeatingCallback<void __cdecl(enum blink::mojom::WebBluetoothResult)>,enum blink::mojom::WebBluetoothResult>,void __cdecl(void)>::RunOnce [0x0161B6F3+19]
	base::debug::TaskAnnotator::RunTask [0x023AFDD2+258]
	blink::scheduler::TaskQueueManager::ProcessTaskFromWorkQueue [0x0207A076+943]
	blink::scheduler::TaskQueueManager::DoWork [0x020790A3+675]
	base::internal::FunctorTraits<void (__thiscall content::WebMediaPlayerMS::*)(bool),void>::Invoke<base::WeakPtr<content::WebMediaPlayerMS>,bool> [0x01251800+26]
	base::internal::InvokeHelper<1,void>::MakeItSo<void (__thiscall content::WebMediaPlayerMS::*)(bool),base::WeakPtr<content::WebMediaPlayerMS>,bool> [0x01251881+34]
	base::internal::Invoker<base::internal::BindState<void (__thiscall content::WebMediaPlayerMS::*)(bool),base::WeakPtr<content::WebMediaPlayerMS>,bool>,void __cdecl(void)>::RunOnce [0x039B40E7+23]
	base::debug::TaskAnnotator::RunTask [0x023AFDD2+258]
	base::internal::IncomingTaskQueue::RunTask [0x023C418B+107]
	base::MessageLoop::RunTask [0x0234F1E6+614]
	base::MessageLoop::DeferOrRunPendingTask [0x0234DE8E+238]
	base::MessageLoop::DoWork [0x0234E714+756]
	base::MessagePumpDefault::Run [0x023C47EB+27]
	base::MessageLoop::Run [0x0234EF77+103]
	base::RunLoop::Run [0x02344FD5+117]
	content::RendererMain [0x0393804B+507]
	content::RunNamedProcessTypeMain [0x015062DE+203]
	content::ContentMainRunnerImpl::Run [0x015061E6+294]
	service_manager::Main [0x02F4CE4F+538]
	content::ContentMain [0x01505931+39]
	content::LaunchTests [0x0212C4E1+552]
	main [0x03B1645A+55]
	__scrt_common_main_seh [0x03AC822A+248] (f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:283)
	BaseThreadInitThunk [0x74B6337A+18]
	RtlInitializeExceptionChain [0x76F692B2+99]
	RtlInitializeExceptionChain [0x76F69285+54]