Version: 003cd61ab7a3e38d8f7fdfe55068c5450ed1bb68
OS: Linux

What steps will reproduce the problem?
(1) Check the "Enable diagnostic packet and event recording" checkbox on chrome://webrtc-internals
(2) Check the "Enable diagnostic packet and event recording" checkbox on chrome://webrtc-internals

What is the expected output?
Recording stops.

What do you see instead?
Chrome core dumps. Stack trace below:

[140880:140880:0520/101303:FATAL:ref_counted.h(322)] Assert failed: ptr_ != __null. 
#0 0x7fbd4e3969be base::debug::StackTrace::StackTrace()
#1 0x7fbd4e3d603f logging::LogMessage::~LogMessage()
#2 0x7fbd42f2fcbb scoped_refptr<>::operator->()
#3 0x7fbd478d2207 content::WebRTCInternals::SetEventLogRecordings()
#4 0x7fbd478db295 content::WebRTCInternalsMessageHandler::OnSetEventLogRecordingsEnabled()
#5 0x7fbd43d18aa7 _ZN4base8internal15RunnableAdapterIMN11cloud_print29PrivetLocalPrintOperationImplEFvbPKNS_15DictionaryValueEEE3RunIPS3_JbS6_EEEvOT_DpOT0_
#6 0x7fbd43d189f3 _ZN4base8internal12InvokeHelperILb0EvNS0_15RunnableAdapterIMN11cloud_print29PrivetLocalPrintOperationImplEFvbPKNS_15DictionaryValueEEEEE8MakeItSoIJPS4_bS7_EEEvSA_DpOT_
#7 0x7fbd478dbd3d _ZN4base8internal7InvokerINS_13IndexSequenceIJLm0ELm1EEEENS0_9BindStateINS0_15RunnableAdapterIMN7content29WebRTCInternalsMessageHandlerEFvbPKNS_9ListValueEEEEFvPS7_bSA_EJNS0_17UnretainedWrapperIS7_EEbEEENS0_12InvokeHelperILb0EvSD_EEFvSA_EE3RunEPNS0_13BindStateBaseEOSA_
#8 0x7fbd43033f16 base::Callback<>::Run()
#9 0x7fbd478ae118 content::WebUIImpl::ProcessWebUIMessage()
#10 0x7fbd478acbdb content::WebUIImpl::OnWebUISend()
#11 0x7fbd4787dffb _ZN4base20DispatchToMethodImplIPN7content15WebContentsImplEMS2_FvRK4GURLRKSsRKNS_9ListValueEEJS4_SsS9_EJLm0ELm1ELm2EEEEvRKT_T0_RKSt5tupleIJDpT1_EENS_13IndexSequenceIJXspT2_EEEE
#12 0x7fbd4787df25 _ZN4base16DispatchToMethodIPN7content15WebContentsImplEMS2_FvRK4GURLRKSsRKNS_9ListValueEEJS4_SsS9_EEEvRKT_T0_RKSt5tupleIJDpT1_EE
#13 0x7fbd478b04cf _ZN3IPC16DispatchToMethodIN7content9WebUIImplEMS2_FvRK4GURLRKSsRKN4base9ListValueEEvSt5tupleIJS3_SsS9_EEEEvPT_T0_PT1_RKT2_
#14 0x7fbd478aeb8b _ZN3IPC8MessageTI26ViewHostMsg_WebUISend_MetaSt5tupleIJ4GURLSsN4base9ListValueEEEvE8DispatchIN7content9WebUIImplESA_vMSA_FvRKS3_RKSsRKS5_EEEbPKNS_7MessageEPT_PT0_PT1_T2_
#15 0x7fbd478ac9f2 content::WebUIImpl::OnMessageReceived()
#16 0x7fbd47852461 content::WebContentsImpl::OnMessageReceived()
#17 0x7fbd47852304 content::WebContentsImpl::OnMessageReceived()
#18 0x7fbd475a988a content::RenderViewHostImpl::OnMessageReceived()
#19 0x7fbd475bc173 content::RenderWidgetHostImpl::OnMessageReceived()
#20 0x7fbd4758b833 content::RenderProcessHostImpl::OnMessageReceived()
#21 0x7fbd464c0718 IPC::ChannelProxy::Context::OnDispatchMessage()
#22 0x7fbd42f45726 _ZN4base8internal15RunnableAdapterIMN7banners20AppBannerDataFetcherEFvRK8SkBitmapEE3RunIRK13scoped_refptrIS3_EJS6_EEEvOT_DpOT0_
#23 0x7fbd464c477e _ZN4base8internal12InvokeHelperILb0EvNS0_15RunnableAdapterIMN3IPC12ChannelProxy7ContextEFvRKNS3_7MessageEEEEE8MakeItSoIJRK13scoped_refptrIS5_ES8_EEEvSB_DpOT_
#24 0x7fbd464c472d _ZN4base8internal7InvokerINS_13IndexSequenceIJLm0ELm1EEEENS0_9BindStateINS0_15RunnableAdapterIMN3IPC12ChannelProxy7ContextEFvRKNS6_7MessageEEEEFvPS8_SB_EJSF_SB_EEENS0_12InvokeHelperILb0EvSE_EEFvvEE3RunEPNS0_13BindStateBaseE
#25 0x7fbd42f30b6e base::Callback<>::Run()
#26 0x7fbd4e3999ce base::debug::TaskAnnotator::RunTask()
#27 0x7fbd4e3ec16c base::MessageLoop::RunTask()
#28 0x7fbd4e3ec408 base::MessageLoop::DeferOrRunPendingTask()
#29 0x7fbd4e3ec662 base::MessageLoop::DoWork()
#30 0x7fbd4e3fe276 base::MessagePumpGlib::Run()
#31 0x7fbd4e3ebb5f base::MessageLoop::RunHandler()
#32 0x7fbd4e46b794 base::RunLoop::Run()
#33 0x7fbd4301febf ChromeBrowserMainParts::MainMessageLoopRun()
#34 0x7fbd46e48969 content::BrowserMainLoop::RunMainMessageLoopParts()
#35 0x7fbd46e51f85 content::BrowserMainRunnerImpl::Run()
#36 0x7fbd46e426f6 content::BrowserMain()
#37 0x7fbd4e3384c6 content::RunNamedProcessTypeMain()
#38 0x7fbd4e33a1b2 content::ContentMainRunnerImpl::Run()
#39 0x7fbd4e337682 content::ContentMain()
#40 0x7fbd42f15a32 ChromeMain
#41 0x7fbd42f159e2 main
#42 0x7fbd3a151ec5 __libc_start_main
#43 0x7fbd42f158e1 <unknown>