Viz crash in mash: FATAL:client_layer_tree_frame_sink.cc(157)] Surface invariants violation

(1) On ToT @ #486152, run chrome --mash
(2) Focus in the omnibox and start typing 'about:extensions'

Expected: Can type in omnibox and navigate without crash.
Actual: Crash! The error seems to come from:
https://cs.chromium.org/chromium/src/components/viz/service/frame_sinks/gpu_compositor_frame_sink.cc?rcl=c94fbe298c74fd17df6691b41caa102b24f48723&l=50

Is there a good label for Viz bugs?

[21449:21449:0713/114752.704759:FATAL:client_layer_tree_frame_sink.cc(157)] Surface invariants violation
#0 0x7f53235f16bb base::debug::StackTrace::StackTrace()
#1 0x7f53235f03fc base::debug::StackTrace::StackTrace()
#2 0x7f532365c157 logging::LogMessage::~LogMessage()
#3 0x7f53189a0829 viz::ClientLayerTreeFrameSink::OnMojoConnectionError()
#4 0x7f53189a2972 _ZN4base8internal13FunctorTraitsIPFvjRKSsEvE6InvokeIJjS3_EEEvS5_DpOT_
#5 0x7f53189a291d _ZN4base8internal12InvokeHelperILb0EvE8MakeItSoIRKPFvjRKSsEJjS5_EEEvOT_DpOT0_
#6 0x7f53189a28bb _ZN4base8internal7InvokerINS0_9BindStateIPFvjRKSsEJEEES5_E7RunImplIRKS6_RKSt5tupleIJEEJEEEvOT_OT0_NS_13IndexSequenceIJXspT1_EEEEOjS4_
#7 0x7f53189a280e _ZN4base8internal7InvokerINS0_9BindStateIPFvjRKSsEJEEES5_E3RunEPNS0_13BindStateBaseEOjS4_
#8 0x7f5321a495e7 _ZNO4base8CallbackIFvjRKSsELNS_8internal8CopyModeE0ELNS4_10RepeatModeE0EE3RunEjS2_
#9 0x7f5321a477ac mojo::InterfaceEndpointClient::NotifyError()
#10 0x7f5321a5d231 mojo::internal::MultiplexRouter::ProcessNotifyErrorTask()
#11 0x7f5321a5b0cd mojo::internal::MultiplexRouter::ProcessTasks()
#12 0x7f5321a5c6e8 mojo::internal::MultiplexRouter::Accept()
#13 0x7f5321a435a0 mojo::FilterChain::Accept()
#14 0x7f5321a37b54 mojo::Connector::ReadSingleMessage()
#15 0x7f5321a38861 mojo::Connector::ReadAllAvailableMessages()
#16 0x7f5321a386ae mojo::Connector::OnHandleReadyInternal()
#17 0x7f5321a385ab mojo::Connector::OnWatcherHandleReady()
#18 0x7f5321a3bd64 _ZN4base8internal13FunctorTraitsIMN4mojo9ConnectorEFvjEvE6InvokeIPS3_JjEEEvS5_OT_DpOT0_
#19 0x7f5321a3bc76 _ZN4base8internal12InvokeHelperILb0EvE8MakeItSoIRKMN4mojo9ConnectorEFvjEJPS5_jEEEvOT_DpOT0_
#20 0x7f5321a3bc07 _ZN4base8internal7InvokerINS0_9BindStateIMN4mojo9ConnectorEFvjEJNS0_17UnretainedWrapperIS4_EEEEEFvjEE7RunImplIRKS6_RKSt5tupleIJS8_EEJLm0EEEEvOT_OT0_NS_13IndexSequenceIJXspT1_EEEEOj
#21 0x7f5321a3bb3c _ZN4base8internal7InvokerINS0_9BindStateIMN4mojo9ConnectorEFvjEJNS0_17UnretainedWrapperIS4_EEEEEFvjEE3RunEPNS0_13BindStateBaseEOj
#22 0x7f5321a337f1 _ZNKR4base8CallbackIFvjELNS_8internal8CopyModeE1ELNS2_10RepeatModeE1EE3RunEj
#23 0x7f5321a3accf mojo::SimpleWatcher::DiscardReadyState()
#24 0x7f5321a3afa4 _ZN4base8internal13FunctorTraitsIPFvRKNS_8CallbackIFvjELNS0_8CopyModeE1ELNS0_10RepeatModeE1EEEjRKN4mojo18HandleSignalsStateEEvE6InvokeIJS8_jSC_EEEvSE_DpOT_
#25 0x7f5321a3af22 _ZN4base8internal12InvokeHelperILb0EvE8MakeItSoIRKPFvRKNS_8CallbackIFvjELNS0_8CopyModeE1ELNS0_10RepeatModeE1EEEjRKN4mojo18HandleSignalsStateEEJSA_jSE_EEEvOT_DpOT0_
#26 0x7f5321a3aeac _ZN4base8internal7InvokerINS0_9BindStateIPFvRKNS_8CallbackIFvjELNS0_8CopyModeE1ELNS0_10RepeatModeE1EEEjRKN4mojo18HandleSignalsStateEEJS7_EEEFvjSD_EE7RunImplIRKSF_RKSt5tupleIJS7_EEJLm0EEEEvOT_OT0_NS_13IndexSequenceIJXspT1_EEEEOjSD_
#27 0x7f5321a3adce _ZN4base8internal7InvokerINS0_9BindStateIPFvRKNS_8CallbackIFvjELNS0_8CopyModeE1ELNS0_10RepeatModeE1EEEjRKN4mojo18HandleSignalsStateEEJS7_EEEFvjSD_EE3RunEPNS0_13BindStateBaseEOjSD_
#28 0x7f53219cf836 _ZNKR4base8CallbackIFvjRKN4mojo18HandleSignalsStateEELNS_8internal8CopyModeE1ELNS6_10RepeatModeE1EE3RunEjS4_
#29 0x7f53219cedc4 mojo::SimpleWatcher::OnHandleReady()
#30 0x7f53219d0421 _ZN4base8internal13FunctorTraitsIMN4mojo13SimpleWatcherEFvijRKNS2_18HandleSignalsStateEEvE6InvokeIRKNS_7WeakPtrIS3_EEJRKiRKjS6_EEEvS8_OT_DpOT0_
#31 0x7f53219d0219 _ZN4base8internal12InvokeHelperILb1EvE8MakeItSoIRKMN4mojo13SimpleWatcherEFvijRKNS4_18HandleSignalsStateEERKNS_7WeakPtrIS5_EEJRKiRKjS8_EEEvOT_OT0_DpOT1_
#32 0x7f53219d0165 _ZN4base8internal7InvokerINS0_9BindStateIMN4mojo13SimpleWatcherEFvijRKNS3_18HandleSignalsStateEEJNS_7WeakPtrIS4_EEijS5_EEEFvvEE7RunImplIRKS9_RKSt5tupleIJSB_ijS5_EEJLm0ELm1ELm2ELm3EEEEvOT_OT0_NS_13IndexSequenceIJXspT1_EEEE
#33 0x7f53219cfffc _ZN4base8internal7InvokerINS0_9BindStateIMN4mojo13SimpleWatcherEFvijRKNS3_18HandleSignalsStateEEJNS_7WeakPtrIS4_EEijS5_EEEFvvEE3RunEPNS0_13BindStateBaseE
#34 0x7f53235b090e _ZNO4base8CallbackIFvvELNS_8internal8CopyModeE0ELNS2_10RepeatModeE0EE3RunEv
#35 0x7f53235f6bc1 base::debug::TaskAnnotator::RunTask()
#36 0x7f532368507e base::MessageLoop::RunTask()
#37 0x7f53236852e7 base::MessageLoop::DeferOrRunPendingTask()
#38 0x7f53236855ff base::MessageLoop::DoWork()
#39 0x7f5323697c9c base::MessagePumpLibevent::Run()
#40 0x7f5323684ae3 base::MessageLoop::Run()
#41 0x7f5323724867 base::RunLoop::Run()
#42 0x55ac2f38c636 ChromeBrowserMainParts::MainMessageLoopRun()
#43 0x7f531c7e26bb content::BrowserMainLoop::RunMainMessageLoopParts()
#44 0x7f531c7edb45 content::BrowserMainRunnerImpl::Run()
#45 0x7f531c7dc498 content::BrowserMain()
#46 0x7f531e13a8f6 content::RunNamedProcessTypeMain()
#47 0x7f531e13ca6e content::ContentMainRunnerImpl::Run()
#48 0x7f531e13954a content::ContentServiceManagerMainDelegate::RunEmbedderProcess()
#49 0x7f5323d0756f service_manager::Main()
#50 0x7f531e13a41b content::ContentMain()
#51 0x55ac2d2cf38c ChromeMain
#52 0x55ac2d2cf282 main
#53 0x7f5306b78f45 __libc_start_main
#54 0x55ac2d2cf164 <unknown>