The majority of failing tests runs into the DCHECK that no reporter is set.

03:35:27.507 14283 worker/2 virtual/android/fullscreen/full-screen-iframe-allowed-video.html crashed, (stderr lines):
03:35:27.508 14283   [1:1:1015/033526:370142682:FATAL:ScriptWrappableVisitor.cpp(37)] Check failed: !m_reporter. 
03:35:27.508 14283   #0 0x7ff468e3aade base::debug::StackTrace::StackTrace()
03:35:27.508 14283   #1 0x7ff468ea862f logging::LogMessage::~LogMessage()
03:35:27.508 14283   #2 0x7ff46016fe7e blink::ScriptWrappableVisitor::TracePrologue()
03:35:27.508 14283   #3 0x7ff465d1c883 v8::internal::IncrementalMarking::StartMarking()
03:35:27.508 14283   #4 0x7ff465d1ebfc v8::internal::IncrementalMarking::Step()
03:35:27.508 14283   #5 0x7ff465d1e704 v8::internal::IncrementalMarking::AdvanceIncrementalMarking()
03:35:27.508 14283   #6 0x7ff465d1ac25 v8::internal::IncrementalMarkingJob::Task::RunInternal()
03:35:27.508 14283   #7 0x7ff4664fad89 _ZN4base8internal13FunctorTraitsIMNS_5TimerEFvvEvE6InvokeIPS2_JEEEvS4_OT_DpOT0_
03:35:27.508 14283   #8 0x7ff4664facb1 _ZN4base8internal12InvokeHelperILb0EvE8MakeItSoIRKMNS_5TimerEFvvEJPS4_EEEvOT_DpOT0_
03:35:27.508 14283   #9 0x7ff4665146c7 _ZN4base8internal7InvokerINS0_9BindStateIMN2v84TaskEFvvEJNS0_12OwnedWrapperIS4_EEEEEFvvEE7RunImplIRKS6_RKSt5tupleIJS8_EEJLm0EEEEvOT_OT0_NS_13IndexSequenceIJXspT1_EEEE
03:35:27.508 14283   #10 0x7ff46651460c _ZN4base8internal7InvokerINS0_9BindStateIMN2v84TaskEFvvEJNS0_12OwnedWrapperIS4_EEEEEFvvEE3RunEPNS0_13BindStateBaseE
03:35:27.508 14283   #11 0x7ff468e409c1 _ZNO4base8internal8RunMixinINS_8CallbackIFvvELNS0_8CopyModeE0ELNS0_10RepeatModeE0EEEE3RunEv
03:35:27.508 14283   #12 0x7ff468e403c9 base::debug::TaskAnnotator::RunTask()
03:35:27.508 14283   #13 0x7ff464dfbe20 blink::scheduler::TaskQueueManager::ProcessTaskFromWorkQueue()
03:35:27.508 14283   #14 0x7ff464df97c2 blink::scheduler::TaskQueueManager::DoWork()
03:35:27.508 14283   #15 0x7ff464e02184 _ZN4base8internal13FunctorTraitsIMN5blink9scheduler16TaskQueueManagerEFvNS_9TimeTicksEbEvE6InvokeIRKNS_7WeakPtrIS4_EEJRKS5_RKbEEEvS7_OT_DpOT0_
03:35:27.508 14283   #16 0x7ff464e02034 _ZN4base8internal12InvokeHelperILb1EvE8MakeItSoIRKMN5blink9scheduler16TaskQueueManagerEFvNS_9TimeTicksEbERKNS_7WeakPtrIS6_EEJRKS7_RKbEEEvOT_OT0_DpOT1_
03:35:27.508 14283   #17 0x7ff464e01f94 _ZN4base8internal7InvokerINS0_9BindStateIMN5blink9scheduler16TaskQueueManagerEFvNS_9TimeTicksEbEJNS_7WeakPtrIS5_EES6_bEEEFvvEE7RunImplIRKS8_RKSt5tupleIJSA_S6_bEEJLm0ELm1ELm2EEEEvOT_OT0_NS_13IndexSequenceIJXspT1_EEEE
03:35:27.508 14283   #18 0x7ff464e01e6c _ZN4base8internal7InvokerINS0_9BindStateIMN5blink9scheduler16TaskQueueManagerEFvNS_9TimeTicksEbEJNS_7WeakPtrIS5_EES6_bEEEFvvEE3RunEPNS0_13BindStateBaseE
03:35:27.508 14283   #19 0x7ff468e409c1 _ZNO4base8internal8RunMixinINS_8CallbackIFvvELNS0_8CopyModeE0ELNS0_10RepeatModeE0EEEE3RunEv
03:35:27.508 14283   #20 0x7ff468e403c9 base::debug::TaskAnnotator::RunTask()
03:35:27.508 14283   #21 0x7ff468ed0f94 base::MessageLoop::RunTask()
03:35:27.508 14283   #22 0x7ff468ed1224 base::MessageLoop::DeferOrRunPendingTask()
03:35:27.508 14283   #23 0x7ff468ed150e base::MessageLoop::DoWork()
03:35:27.508 14283   #24 0x7ff468ee8de3 base::MessagePumpDefault::Run()
03:35:27.508 14283   #25 0x7ff468ed0b0a base::MessageLoop::RunHandler()
03:35:27.508 14283   #26 0x7ff468f77214 base::RunLoop::Run()
03:35:27.508 14283   #27 0x7ff46b9c43cc content::RendererMain()
03:35:27.508 14283   #28 0x7ff46bd82dbe content::RunZygote()
03:35:27.509 14283   #29 0x7ff46bd831d0 content::RunNamedProcessTypeMain()
03:35:27.509 14283   #30 0x7ff46bd85602 content::ContentMainRunnerImpl::Run()
03:35:27.509 14283   #31 0x7ff46bd82462 content::ContentMain()
03:35:27.509 14283   #32 0x000000486d89 main
03:35:27.509 14283   #33 0x7ff45c509f45 __libc_start_main
03:35:27.509 14283   #34 0x000000486c75 <unknown>