The issue is that the error page reloads itself after it gets more data, but IsErrorPage isn't true.

This is the callstack in the renderer which leads to the second NetErrorTabHelper::DidFinishNavigation call
>	content.dll!content::RenderFrameImpl::didStartProvisionalLoad(blink::WebLocalFrame * frame, double triggering_event_time) Line 3253	C++
 	blink_web.dll!blink::FrameLoaderClientImpl::dispatchDidStartProvisionalLoad(double triggeringEventTime) Line 449	C++
 	blink_core.dll!blink::FrameLoader::startLoad(blink::FrameLoadRequest & frameLoadRequest, blink::FrameLoadType type, blink::NavigationPolicy navigationPolicy) Line 1468	C++
 	blink_core.dll!blink::FrameLoader::load(const blink::FrameLoadRequest & passedRequest, blink::FrameLoadType frameLoadType, blink::HistoryItem * historyItem, blink::HistoryLoadType historyLoadType) Line 1024	C++
 	blink_web.dll!blink::WebLocalFrameImpl::loadData(const blink::WebData & data, const blink::WebString & mimeType, const blink::WebString & textEncoding, const blink::WebURL & baseURL, const blink::WebURL & unreachableURL, bool replace, blink::WebFrameLoadType webFrameLoadType, const blink::WebHistoryItem & item, blink::WebHistoryLoadType webHistoryLoadType, bool isClientRedirect) Line 1910	C++
 	blink_web.dll!blink::WebLocalFrameImpl::loadHTMLString(const blink::WebData & data, const blink::WebURL & baseURL, const blink::WebURL & unreachableURL, bool replace) Line 880	C++
 	browser_tests.exe!NetErrorHelper::LoadErrorPage(const std::basic_string<char,std::char_traits<char>,std::allocator<char> > & html, const GURL & failed_url) Line 227	C++
 	browser_tests.exe!error_page::NetErrorHelperCore::OnNavigationCorrectionsFetched(const std::basic_string<char,std::char_traits<char>,std::allocator<char> > & corrections, bool is_rtl) Line 863	C++
 	browser_tests.exe!NetErrorHelper::OnNavigationCorrectionsFetched(const blink::WebURLResponse & response, const std::basic_string<char,std::char_traits<char>,std::allocator<char> > & data) Line 368	C++
 	browser_tests.exe!base::internal::FunctorTraits<void (__thiscall NetErrorHelper::*)(blink::WebURLResponse const &,std::basic_string<char,std::char_traits<char>,std::allocator<char> > const &),void>::Invoke<NetErrorHelper *,blink::WebURLResponse const &,std::basic_string<char,std::char_traits<char>,std::allocator<char> > const &>(void(NetErrorHelper::*)(const blink::WebURLResponse &, const std::basic_string<char,std::char_traits<char>,std::allocator<char> > &) method, NetErrorHelper * && receiver_ptr, const blink::WebURLResponse & <args_0>, const std::basic_string<char,std::char_traits<char>,std::allocator<char> > & <args_1>) Line 215	C++
 	browser_tests.exe!base::internal::InvokeHelper<0,void>::MakeItSo<void (__thiscall NetErrorHelper::*const &)(blink::WebURLResponse const &,std::basic_string<char,std::char_traits<char>,std::allocator<char> > const &),NetErrorHelper *,blink::WebURLResponse const &,std::basic_string<char,std::char_traits<char>,std::allocator<char> > const &>(void(NetErrorHelper::*)(const blink::WebURLResponse &, const std::basic_string<char,std::char_traits<char>,std::allocator<char> > &) & functor, NetErrorHelper * && <args_0>, const blink::WebURLResponse & <args_1>, const std::basic_string<char,std::char_traits<char>,std::allocator<char> > & <args_2>) Line 285	C++
 	browser_tests.exe!base::internal::Invoker<base::internal::BindState<void (__thiscall NetErrorHelper::*)(blink::WebURLResponse const &,std::basic_string<char,std::char_traits<char>,std::allocator<char> > const &),base::internal::UnretainedWrapper<NetErrorHelper> >,void __cdecl(blink::WebURLResponse const &,std::basic_string<char,std::char_traits<char>,std::allocator<char> > const &)>::RunImpl<void (__thiscall NetErrorHelper::*const &)(blink::WebURLResponse const &,std::basic_string<char,std::char_traits<char>,std::allocator<char> > const &),std::tuple<base::internal::UnretainedWrapper<NetErrorHelper> > const &,0>(void(NetErrorHelper::*)(const blink::WebURLResponse &, const std::basic_string<char,std::char_traits<char>,std::allocator<char> > &) & functor, const std::tuple<base::internal::UnretainedWrapper<NetErrorHelper> > & bound, base::IndexSequence<0> __formal, const blink::WebURLResponse & <unbound_args_0>, const std::basic_string<char,std::char_traits<char>,std::allocator<char> > & <unbound_args_1>) Line 361	C++
 	browser_tests.exe!base::internal::Invoker<base::internal::BindState<void (__thiscall NetErrorHelper::*)(blink::WebURLResponse const &,std::basic_string<char,std::char_traits<char>,std::allocator<char> > const &),base::internal::UnretainedWrapper<NetErrorHelper> >,void __cdecl(blink::WebURLResponse const &,std::basic_string<char,std::char_traits<char>,std::allocator<char> > const &)>::Run(base::internal::BindStateBase * base, const blink::WebURLResponse & <unbound_args_0>, const std::basic_string<char,std::char_traits<char>,std::allocator<char> > & <unbound_args_1>) Line 339	C++
 	content.dll!base::internal::RunMixin<base::Callback<void __cdecl(blink::WebURLResponse const &,std::basic_string<char,std::char_traits<char>,std::allocator<char> > const &),1,1> >::Run(const blink::WebURLResponse & <args_0>, const std::basic_string<char,std::char_traits<char>,std::allocator<char> > & <args_1>) Line 64	C++
 	content.dll!content::ResourceFetcherImpl::OnLoadComplete() Line 144	C++


WebContentsImpl::DidStartProvisionalLoad  does have is_error_page true, since the url there is "data:text/html,chromewebdata". However by the time this goes to the NavigationHandle, the url is just the mock url. The net::Error on the navigation handle is net::OK.


It seems like we want the NavigationHandle to know that what's (re) loaded is the error page.



Repro:
Apply this patch:
https://codereview.chromium.org/2345913002/#ps20001
but remove this line:
    (navigation_handle->IsSynchronousNavigation() &&
        navigation_handle->GetURL() == error_page_url_)) {


Then run
DnsProbeBrowserTest.NoInternetProbeResultWithBrokenCorrections

This happens with and without PlzNavigate.