The EnumerateAttachedDevicesOnBlockingThread task should be posted to a TaskRunner obtained via CreateCOMSTATaskRunnerWithTraits().

Call stack:

  base.dll!base::debug::BreakDebugger() Line 21
  base.dll!logging::LogMessage::~LogMessage() Line 787
  base.dll!base::win::AssertComInitialized(const char * message) Line 72
  base.dll!base::win::`anonymous namespace'::HookManager::DCheckedCoCreateInstance(const _GUID & rclsid, IUnknown * pUnkOuter, unsigned long dwClsContext, const _GUID & riid, void * * ppv) Line 247
> chrome.dll!storage_monitor::`anonymous namespace'::GetPortableDeviceManager(base::win::ScopedComPtr<IPortableDeviceManager> * portable_device_mgr) Line 390
  chrome.dll!storage_monitor::`anonymous namespace'::EnumerateAttachedDevicesOnBlockingThread(std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > * devices) Line 410
  chrome.dll!base::internal::FunctorTraits<bool (__cdecl*)(std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > *),void>::Invoke<std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > * const &>(bool(*)(std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > *) function, std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > * const & <args_0>) Line 151
  chrome.dll!base::internal::InvokeHelper<0,bool>::MakeItSo<bool (__cdecl*const &)(std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > *),std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > * const &>(bool(*)(std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > *) & functor, std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > * const & <args_0>) Line 262
  chrome.dll!base::internal::Invoker<base::internal::BindState<bool (__cdecl*)(std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > *),std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > *>,bool __cdecl(void)>::RunImpl<bool (__cdecl*const &)(std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > *),std::tuple<std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > *> const &,0>(bool(*)(std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > *) & functor, const std::tuple<std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > *> & bound, base::IndexSequence<0> __formal) Line 338
  chrome.dll!base::internal::Invoker<base::internal::BindState<bool (__cdecl*)(std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > *),std::vector<storage_monitor::PortableDeviceWatcherWin::DeviceDetails,std::allocator<storage_monitor::PortableDeviceWatcherWin::DeviceDetails> > *>,bool __cdecl(void)>::Run(base::internal::BindStateBase * base) Line 316
  chrome.dll!base::Callback<bool __cdecl(void),0,0>::Run() Line 91
  chrome.dll!base::internal::ReturnAsParamAdapter<bool>(base::Callback<bool __cdecl(void),0,0> func, bool * result) Line 20
  chrome.dll!base::internal::FunctorTraits<void (__cdecl*)(base::Callback<bool __cdecl(void),0,0>,bool *),void>::Invoke<base::Callback<bool __cdecl(void),0,0>,bool *>(void(*)(base::Callback<bool __cdecl(void),0,0>, bool *) function, base::Callback<bool __cdecl(void),0,0> && <args_0>, bool * && <args_1>) Line 151
  chrome.dll!base::internal::InvokeHelper<0,void>::MakeItSo<void (__cdecl*)(base::Callback<bool __cdecl(void),0,0>,bool *),base::Callback<bool __cdecl(void),0,0>,bool *>(void(*)(base::Callback<bool __cdecl(void),0,0>, bool *) && functor, base::Callback<bool __cdecl(void),0,0> && <args_0>, bool * && <args_1>) Line 262
  chrome.dll!base::internal::Invoker<base::internal::BindState<void (__cdecl*)(base::Callback<bool __cdecl(void),0,0>,bool *),base::Callback<bool __cdecl(void),0,0>,bool *>,void __cdecl(void)>::RunImpl<void (__cdecl*)(base::Callback<bool __cdecl(void),0,0>,bool *),std::tuple<base::Callback<bool __cdecl(void),0,0>,bool *>,0,1>(void(*)(base::Callback<bool __cdecl(void),0,0>, bool *) && functor, std::tuple<base::Callback<bool __cdecl(void),0,0>,bool *> && bound, base::IndexSequence<0,1> __formal) Line 338
  chrome.dll!base::internal::Invoker<base::internal::BindState<void (__cdecl*)(base::Callback<bool __cdecl(void),0,0>,bool *),base::Callback<bool __cdecl(void),0,0>,bool *>,void __cdecl(void)>::RunOnce(base::internal::BindStateBase * base) Line 303
  base.dll!base::Callback<void __cdecl(void),0,0>::Run() Line 91
  base.dll!base::`anonymous namespace'::PostTaskAndReplyRelay::RunTaskAndPostReply() Line 46
  base.dll!base::internal::FunctorTraits<void (__thiscall base::`anonymous namespace'::PostTaskAndReplyRelay::*)(void),void>::Invoke<base::`anonymous namespace'::PostTaskAndReplyRelay *>(void(base::`anonymous-namespace'::PostTaskAndReplyRelay::*)() method, base::`anonymous-namespace'::PostTaskAndReplyRelay * && receiver_ptr) Line 197
  base.dll!base::internal::InvokeHelper<0,void>::MakeItSo<void (__thiscall base::`anonymous namespace'::PostTaskAndReplyRelay::*)(void),base::A0xe667f948::PostTaskAndReplyRelay *>(void(base::`anonymous-namespace'::PostTaskAndReplyRelay::*)() && functor, base::`anonymous-namespace'::PostTaskAndReplyRelay * && <args_0>) Line 262
  base.dll!base::internal::Invoker<base::internal::BindState<void (__thiscall base::`anonymous namespace'::PostTaskAndReplyRelay::*)(void),base::internal::UnretainedWrapper<base::`anonymous namespace'::PostTaskAndReplyRelay> >,void __cdecl(void)>::RunImpl<void (__thiscall base::`anonymous namespace'::PostTaskAndReplyRelay::*)(void),std::tuple<base::internal::UnretainedWrapper<base::`anonymous namespace'::PostTaskAndReplyRelay> >,0>(void(base::`anonymous-namespace'::PostTaskAndReplyRelay::*)() && functor, std::tuple<base::internal::UnretainedWrapper<base::`anonymous namespace'::PostTaskAndReplyRelay> > && bound, base::IndexSequence<0> __formal) Line 338
  base.dll!base::internal::Invoker<base::internal::BindState<void (__thiscall base::`anonymous namespace'::PostTaskAndReplyRelay::*)(void),base::internal::UnretainedWrapper<base::`anonymous namespace'::PostTaskAndReplyRelay> >,void __cdecl(void)>::RunOnce(base::internal::BindStateBase * base) Line 303
  base.dll!base::Callback<void __cdecl(void),0,0>::Run() Line 91
  base.dll!base::debug::TaskAnnotator::RunTask(const char * queue_function, base::PendingTask * pending_task) Line 61
  base.dll!base::internal::TaskTracker::PerformRunTask(std::unique_ptr<base::internal::Task,std::default_delete<base::internal::Task> > task, base::internal::Sequence * sequence) Line 335
  base.dll!base::internal::TaskTracker::RunNextTask(base::internal::Sequence * sequence) Line 252
  base.dll!base::internal::SchedulerWorker::Thread::ThreadMain() Line 84
  base.dll!base::`anonymous namespace'::ThreadFunc(void * params) Line 91