It's SafeBrowsing. This is much higher than a P3. It's also a regression.

	Last event: dbc.bd4: Break instruction exception - code 80000003 (first/second chance not available)
	  debugger time: Thu May 18 22:30:25.642 2017 (UTC - 7:00)
	ChildEBP RetAddr  Args to Child              
	0018e20c 6f4d2011 09a3c240 0a6cb920 09a3c0b8 base!base::WeakPtr<base::win::ObjectWatcher>::get+0x43
	*** WARNING: Unable to verify checksum for chrome.dll
	WARNING: Stack unwind information not available. Following frames may be wrong.
	0018e23c 08f6ba04 09a3c240 0a6cb920 09a3c0b8 ucrtbased!invalid_parameter+0xa1
	0018e260 08f6ba73 ffffffff 0018e28c 0018e280 chrome_30d0000!std::_Vector_const_iterator<std::_Vector_val<std::_Simple_types<subresource_filter::SubresourceFilterSafeBrowsingClient::CheckResult> > >::operator+=+0xb4
	0018e270 08f6baa5 ffffffff 0018e28c 0018e29c chrome_30d0000!std::_Vector_iterator<std::_Vector_val<std::_Simple_types<subresource_filter::SubresourceFilterSafeBrowsingClient::CheckResult> > >::operator+=+0x13
	0018e280 08f6b921 00000001 24f277e0 0018e2ac chrome_30d0000!std::_Vector_iterator<std::_Vector_val<std::_Simple_types<subresource_filter::SubresourceFilterSafeBrowsingClient::CheckResult> > >::operator-=+0x15
	0018e29c 08f6d462 0018e2b8 00000001 24f277e0 chrome_30d0000!std::_Vector_iterator<std::_Vector_val<std::_Simple_types<subresource_filter::SubresourceFilterSafeBrowsingClient::CheckResult> > >::operator-+0x21
	0018e2cc 08f6be2e 6f61e4e0 6f66e430 0018e2e8 chrome_30d0000!std::vector<subresource_filter::SubresourceFilterSafeBrowsingClient::CheckResult,std::allocator<subresource_filter::SubresourceFilterSafeBrowsingClient::CheckResult> >::back+0x22
	0018e554 08f6cb16 12413c45 24f05f80 24f05f80 chrome_30d0000!subresource_filter::SubresourceFilterSafeBrowsingActivationThrottle::NotifyResult+0xae
	*** WARNING: Unable to verify checksum for content.dll
	0018e568 12414e8a 0018e63c 1021ce6a 00000bd4 chrome_30d0000!subresource_filter::SubresourceFilterSafeBrowsingActivationThrottle::WillProcessResponse+0x36
	0018e8a0 1241877b 24ee3da0 00000001 0118e97c content!content::NavigationHandleImpl::CheckWillProcessResponse+0x1ca
	0018e9c8 126dfdfd 2436c8d0 24f06bb0 00000009 content!content::NavigationHandleImpl::WillProcessResponse+0x1db
	0018eba4 126dc133 24fd3688 00000003 00000002 content!content::NavigationResourceThrottle::WillProcessResponse+0x67d
	0018ebdc 126dc923 126dfbd0 24f1b3f0 24f1b3ec content!base::internal::FunctorTraits<void (__cdecl*)(base::Callback<void __cdecl(enum content::NavigationThrottle::ThrottleCheckResult),1,1>,int,int,scoped_refptr<net::HttpResponseHeaders>,enum net::HttpResponseInfo::ConnectionInfo,content::SSLStatus const &,content::GlobalRequestID const &,bool,bool,bool,base::Callback<void __cdecl(void),1,1> const &,std::unique_ptr<content::NavigationData,std::default_delete<content::NavigationData> >),void>::Invoke<base::Callback<void __cdecl(enum content::NavigationThrottle::ThrottleCheckResult),1,1> const &,int const &,int const &,scoped_refptr<net::HttpResponseHeaders> const &,enum net::HttpResponseInfo::ConnectionInfo const &,content::SSLStatus const &,content::GlobalRequestID const &,bool const &,bool const &,bool const &,base::Callback<void __cdecl(void),1,1> const &,std::unique_ptr<content::NavigationData,std::default_delete<content::NavigationData> > >+0xc3
	0018ec18 126dcf9e 24f1b38c 24f1b3f0 24f1b3ec content!base::internal::InvokeHelper<0,void>::MakeItSo<void (__cdecl*const &)(base::Callback<void __cdecl(enum content::NavigationThrottle::ThrottleCheckResult),1,1>,int,int,scoped_refptr<net::HttpResponseHeaders>,enum net::HttpResponseInfo::ConnectionInfo,content::SSLStatus const &,content::GlobalRequestID const &,bool,bool,bool,base::Callback<void __cdecl(void),1,1> const &,std::unique_ptr<content::NavigationData,std::default_delete<content::NavigationData> >),base::Callback<void __cdecl(enum content::NavigationThrottle::ThrottleCheckResult),1,1> const &,int const &,int const &,scoped_refptr<net::HttpResponseHeaders> const &,enum net::HttpResponseInfo::ConnectionInfo const &,content::SSLStatus const &,content::GlobalRequestID const &,bool const &,bool const &,bool const &,base::Callback<void __cdecl(void),1,1> const &,std::unique_ptr<content::NavigationData,std::default_delete<content::NavigationData> > >+0xb3
	0018ec58 126df364 24f1b38c 24f1b390 00000010 content!base::internal::Invoker<base::internal::BindState<void (__cdecl*)(base::Callback<void __cdecl(enum content::NavigationThrottle::ThrottleCheckResult),1,1>,int,int,scoped_refptr<net::HttpResponseHeaders>,enum net::HttpResponseInfo::ConnectionInfo,content::SSLStatus const &,content::GlobalRequestID const &,bool,bool,bool,base::Callback<void __cdecl(void),1,1> const &,std::unique_ptr<content::NavigationData,std::default_delete<content::NavigationData> >),base::Callback<void __cdecl(enum content::NavigationThrottle::ThrottleCheckResult),1,1>,int,int,scoped_refptr<net::HttpResponseHeaders>,enum net::HttpResponseInfo::ConnectionInfo,content::SSLStatus,content::GlobalRequestID,bool,bool,bool,base::Callback<void __cdecl(void),1,1>,base::internal::PassedWrapper<std::unique_ptr<content::NavigationData,std::default_delete<content::NavigationData> > > >,void __cdecl(void)>::RunImpl<void (__cdecl*const &)(base::Callback<void __cdecl(enum content::NavigationThrottle::ThrottleCheckResult),1,1>,int,int,scoped_refptr<net::HttpResponseHeaders>,enum net::HttpResponseInfo::ConnectionInfo,content::SSLStatus const &,content::GlobalRequestID const &,bool,bool,bool,base::Callback<void __cdecl(void),1,1> const &,std::unique_ptr<content::NavigationData,std::default_delete<content::NavigationData> >),std::tuple<base::Callback<void __cdecl(enum content::NavigationThrottle::ThrottleCheckResult),1,1>,int,int,scoped_refptr<net::HttpResponseHeaders>,enum net::HttpResponseInfo::ConnectionInfo,content::SSLStatus,content::GlobalRequestID,bool,bool,bool,base::Callback<void __cdecl(void),1,1>,base::internal::PassedWrapper<std::unique_ptr<content::NavigationData,std::default_delete<content::NavigationData> > > > const &,0,1,2,3,4,5,6,7,8,9,10,11>+0x18e
	0018ec74 10049a25 24f1b378 10d1183e 0018ef90 content!base::internal::Invoker<base::internal::BindState<void (__cdecl*)(base::Callback<void __cdecl(enum content::NavigationThrottle::ThrottleCheckResult),1,1>,int,int,scoped_refptr<net::HttpResponseHeaders>,enum net::HttpResponseInfo::ConnectionInfo,content::SSLStatus const &,content::GlobalRequestID const &,bool,bool,bool,base::Callback<void __cdecl(void),1,1> const &,std::unique_ptr<content::NavigationData,std::default_delete<content::NavigationData> >),base::Callback<void __cdecl(enum content::NavigationThrottle::ThrottleCheckResult),1,1>,int,int,scoped_refptr<net::HttpResponseHeaders>,enum net::HttpResponseInfo::ConnectionInfo,content::SSLStatus,content::GlobalRequestID,bool,bool,bool,base::Callback<void __cdecl(void),1,1>,base::internal::PassedWrapper<std::unique_ptr<content::NavigationData,std::default_delete<content::NavigationData> > > >,void __cdecl(void)>::Run+0x24
	0018ec8c 100b449c 00000000 0018eca4 0018ee30 base!base::Callback<void __cdecl(void),0,0>::Run+0x35
	0018ed5c 1012fdc2 103f82bc 0018ef80 00000000 base!base::debug::TaskAnnotator::RunTask+0x1dc
	0018ef64 1012e212 0018ef80 008b3798 0018f018 base!base::MessageLoop::RunTask+0x272
	0018ef78 1012e852 24fd4fa8 028d6abe 00000000 base!base::MessageLoop::DeferOrRunPendingTask+0x32
	0018f018 101367b3 fffde000 00859dc8 0018f04c base!base::MessageLoop::DoWork+0xf2
	0018f02c 1013774b 008b3798 100f0900 00000001 base!base::MessagePumpForUI::DoRunLoop+0x43
	0018f060 1012fa4f 008b3798 007d0000 00000000 base!base::MessagePumpWin::Run+0x7b
	0018f138 101ee0ea fffffffe 0018f154 07e14d6e base!base::MessageLoop::Run+0xbf
	0018f2c8 04d35688 24d3884e 14c1df76 00000000 base!base::RunLoop::Run+0xba
	0018f3ac 1205d221 008a46e0 0018f3d0 10040de6 chrome_30d0000!ChromeBrowserMainParts::MainMessageLoopRun+0xf8
	0018f424 12063383 00000000 24c281e0 0018f448 content!content::BrowserMainLoop::RunMainMessageLoopParts+0xe1
	0018f598 1204ecfb 00000000 0018f5bc 037419d5 content!content::BrowserMainRunnerImpl::Run+0xf3
	0018f5c0 13b642b7 0018f808 01260120 00837f84 content!content::BrowserMain+0x9b
	0018f68c 13b6415c 0018f884 0018f808 0018fbe8 content!content::RunNamedProcessTypeMain+0x87
	0018f8a4 13b61f34 0018fb00 00861dc0 0018faf4 content!content::ContentMainRunnerImpl::Run+0x23c
	*** WARNING: Unable to verify checksum for embedder.dll
	0018f8b4 011382b9 01b8923c 00000001 0018f8e4 content!content::ContentServiceManagerMainDelegate::RunEmbedderProcess+0x24
	0018faf4 13b62429 0018fb20 14e76028 0018fbe8 embedder!service_manager::Main+0x309
	0018fb24 0373cfb8 0018fc04 77001985 037fd4b8 content!content::ContentMain+0x29
	*** WARNING: Unable to verify checksum for chrome.exe
	0018fc34 0042f5fd 00400000 0018fc54 f8068d45 chrome_30d0000!ChromeMain+0x148
	0018fd10 0042a4b0 00400000 f8068d45 00000009 chrome!MainDllLoader::Launch+0x33d
	0018ff08 004ea89e 00400000 00000000 007d28ac chrome!wWinMain+0x240
	0018ff20 004ea700 f01a676a 00000000 00000000 chrome!invoke_main+0x1e
	0018ff78 004ea59d 0018ff88 004ea8b8 0018ff94 chrome!__scrt_common_main_seh+0x150
	0018ff80 004ea8b8 0018ff94 763c337a fffde000 chrome!__scrt_common_main+0xd
	*** WARNING: Unable to verify checksum for kernel32.dll
	*** ERROR: Symbol file could not be found.  Defaulted to export symbols for kernel32.dll - 
	0018ff88 763c337a fffde000 0018ffd4 76fc92b2 chrome!wWinMainCRTStartup+0x8
	0018ff94 76fc92b2 fffde000 759c947c 00000000 kernel32!BaseThreadInitThunk+0x12
	0018ffd4 76fc9285 00411397 fffde000 ffffffff ntdll!RtlInitializeExceptionChain+0x63
	0018ffec 00000000 00411397 fffde000 00000000 ntdll!RtlInitializeExceptionChain+0x36

melandory@ -- I see subresource_filter::SubresourceFilterSafeBrowsingClient in the stack so assigning to you.

Also failing on Linux Debug Intel 530. https://build.chromium.org/p/chromium.gpu.fyi/builders/Linux%20Debug%20%28Intel%20HD%20530%29/builds/1744

Suspected CL in range is https://codereview.chromium.org/2889913002 which is being reverted right now.

Some of the debug bots are already cycling back green: https://build.chromium.org/p/chromium.gpu.fyi/builders/Win7%20Debug%20%28AMD%29

Sorry this slipped through the cracks in my email. It looks like the same underlying problem as issue 723960 (calling vector::back on an empty vector). It should be fixed now.