UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3651.0 Safari/537.36

Steps to reproduce the problem:
1. Compile views_examples_with_content_exe with dcheck_is_always_on
2. Run views_examples_with_content_exe

What is the expected behavior?
Correct running example

What went wrong?
DCHECK happens at https://chromium.googlesource.com/chromium/src/+blame/master/content/browser/scheduler/responsiveness/native_event_observer_mac.mm#15 (Check failed: [NSApp conformsToProtocol:@protocol(NativeEventProcessor)])

content::responsiveness::NativeEventObserver::RegisterObserver()
content::responsiveness::NativeEventObserver::NativeEventObserver(base::RepeatingCallback<void (void const*)>, base::RepeatingCallback<void (void const*)>)
content::responsiveness::NativeEventObserver::NativeEventObserver(base::RepeatingCallback<void (void const*)>, base::RepeatingCallback<void (void const*)>)
std::__1::__unique_if<content::responsiveness::NativeEventObserver>::__unique_single std::__1::make_unique<content::responsiveness::NativeEventObserver, base::RepeatingCallback<void (void const*)>, base::RepeatingCallback<void (void const*)> >(base::RepeatingCallback<void (void const*)>&&, base::RepeatingCallback<void (void const*)>&&)
content::responsiveness::Watcher::CreateNativeEventObserver()
content::responsiveness::Watcher::SetUp()
content::BrowserMainLoop::BrowserThreadsStarted()
int base::internal::FunctorTraits<int (content::BrowserMainLoop::*)(), void>::Invoke<int (content::BrowserMainLoop::*)(), content::BrowserMainLoop*>(int (content::BrowserMainLoop::*)(), content::BrowserMainLoop*&&)
int base::internal::InvokeHelper<false, int>::MakeItSo<int (content::BrowserMainLoop::* const&)(), content::BrowserMainLoop*>(int (content::BrowserMainLoop::* const&&&)(), content::BrowserMainLoop*&&)
int base::internal::Invoker<base::internal::BindState<int (content::BrowserMainLoop::*)(), base::internal::UnretainedWrapper<content::BrowserMainLoop> >, int ()>::RunImpl<int (content::BrowserMainLoop::* const&)(), std::__1::tuple<base::internal::UnretainedWrapper<content::BrowserMainLoop> > const&, 0ul>(int (content::BrowserMainLoop::* const&&&)(), std::__1::tuple<base::internal::UnretainedWrapper<content::BrowserMainLoop> > const&&&, std::__1::integer_sequence<unsigned long, 0ul>)
base::internal::Invoker<base::internal::BindState<int (content::BrowserMainLoop::*)(), base::internal::UnretainedWrapper<content::BrowserMainLoop> >, int ()>::Run(base::internal::BindStateBase*)
base::RepeatingCallback<int ()>::Run() const &
content::StartupTaskRunner::RunAllTasksNow()
content::BrowserMainLoop::CreateStartupTasks()
content::BrowserMainRunnerImpl::Initialize(content::MainFunctionParams const&)
content::BrowserMain(content::MainFunctionParams const&)
content::RunBrowserProcessMain(content::MainFunctionParams const&, content::ContentMainDelegate*)
content::ContentMainRunnerImpl::RunServiceManager(content::MainFunctionParams&, bool)
content::ContentMainRunnerImpl::Run(bool)
content::ContentServiceManagerMainDelegate::RunEmbedderProcess()
service_manager::Main(service_manager::MainParams const&)
content::ContentMain(content::ContentMainParams const&)
ui::ViewsContentClient::RunMain()
main
start

Did this work before? Yes Before https://chromium.googlesource.com/chromium/src/+/3f51ab68a022dd6091a2a570424357e848752d00

Chrome version: 73.0.3651.0  Channel: dev
OS Version: OS X 10.12.6
Flash Version: 

All examples that do not register NativeEventProcessor derived applications do crashes.