Steps to reproduce:
(1) Open Chrome
(2) Try to install the extension ChromeVox from Chrome Web Store

Expected result:
ChromeVox is installed.

Actual result:
Chrome crashes.

Happened on:
Chromium	66.0.3353.0 (Developer Build) (64-bit)
Revision	6d0f343d1a2c7662f62b1b3e3b03c2339ed7ae33-refs/heads/master@{#538423}
OS	Linux

Stack trace:
[112989:112989:0227/142534.359262:FATAL:thread_restrictions.cc(29)] Check failed: !g_blocking_disallowed.Get().Get(). Function marked as blocking was called from a scope that disallows blocking! If this task is running inside the TaskScheduler, it needs to have MayBlock() in its TaskTraits. Otherwise, consider making this blocking work asynchronous or, as a last resort, you may use ScopedAllowBlocking in a narrow scope.
#0 0x5600868b9afc base::debug::StackTrace::StackTrace()
#1 0x5600868da17c logging::LogMessage::~LogMessage()
#2 0x56008694a0f6 base::AssertBlockingAllowed()
#3 0x5600868cda0e base::PathExists()
#4 0x560086693828 Profile::CreateProfile()
#5 0x5600866bb438 ProfileManager::CreateProfileHelper()
#6 0x5600866b4548 ProfileManager::CreateAndInitializeProfile()
#7 0x5600866b427c ProfileManager::GetProfile()
#8 0x5600866b4110 ProfileManager::GetActiveUserOrOffTheRecordProfileFromPath()
#9 0x5600866b416c ProfileManager::GetActiveUserProfile()
#10 0x560088b10948 extensions::AutomationEventRouter::AutomationEventRouter()
#11 0x560088b10881 base::Singleton<>::get()
#12 0x560088b0f59c extensions::AutomationInternalEnableDesktopFunction::Run()
#13 0x56008551d8a8 ExtensionFunction::RunWithValidation()
#14 0x56008552025d extensions::ExtensionFunctionDispatcher::DispatchWithCallbackInternal()
#15 0x56008551fd6a extensions::ExtensionFunctionDispatcher::Dispatch()
#16 0x560085544dd9 _ZN3IPC8MessageTI29ExtensionHostMsg_Request_MetaNSt3__15tupleIJ31ExtensionHostMsg_Request_ParamsEEEvE8DispatchIN10extensions28ExtensionWebContentsObserverES9_N7content15RenderFrameHostEMS9_FvPSB_RKS4_EEEbPKNS_7MessageEPT_PT0_PT1_T2_
#17 0x560085544d19 extensions::ExtensionWebContentsObserver::OnMessageReceived()
#18 0x56008880c97f extensions::ChromeExtensionWebContentsObserver::OnMessageReceived()
#19 0x5600852e2a65 content::WebContentsImpl::OnMessageReceived()
#20 0x560084f968d6 content::RenderFrameHostImpl::OnMessageReceived()
#21 0x5600851a087d content::RenderProcessHostImpl::OnMessageReceived()
#22 0x560086f29091 IPC::ChannelProxy::Context::OnDispatchMessage()
#23 0x560084d28438 _ZN4base8internal7InvokerINS0_9BindStateIMN7content8protocol12_GLOBAL__N_115CookieRetrieverEFvRKNSt3__16vectorIN3net15CanonicalCookieENS7_9allocatorISA_EEEEEJ13scoped_refptrIS6_ESD_EEEFvvEE7RunOnceEPNS0_13BindStateBaseE
#24 0x5600868bb0ea base::debug::TaskAnnotator::RunTask()
#25 0x5600868e1fc6 base::internal::IncomingTaskQueue::RunTask()
#26 0x5600868e0447 base::MessageLoop::RunTask()
#27 0x5600868e086a base::MessageLoop::DeferOrRunPendingTask()
#28 0x5600868e0afe base::MessageLoop::DoWork()
#29 0x5600868e4d5f base::(anonymous namespace)::WorkSourceDispatch()
#30 0x7fa5741d47f7 g_main_context_dispatch
#31 0x7fa5741d4a60 <unknown>
#32 0x7fa5741d4b0c g_main_context_iteration
#33 0x5600868e4b12 base::MessagePumpGlib::Run()
#34 0x5600868dfcbc base::MessageLoop::Run()
#35 0x560086910ce6 base::RunLoop::Run()
#36 0x560086530047 ChromeBrowserMainParts::MainMessageLoopRun()
#37 0x560084e26dd7 content::BrowserMainLoop::RunMainMessageLoopParts()
#38 0x560084e2a5f3 content::BrowserMainRunnerImpl::Run()
#39 0x560084e22c5a content::BrowserMain()
#40 0x5600864feb1b content::RunNamedProcessTypeMain()
#41 0x5600864ffc67 content::ContentMainRunnerImpl::Run()
#42 0x56008650cd7a service_manager::Main()
#43 0x5600864fdfb1 content::ContentMain()
#44 0x56008413e1cb ChromeMain
#45 0x7fa5703632b1 __libc_start_main
#46 0x56008413e02a _start