Bug 1840182 - Do not create new XHR channel during shutdown r=necko-reviewers,kershaw

Differential Revision: https://phabricator.services.mozilla.com/D213018

dom/xhr/XMLHttpRequestMainThread.cpp

@@ -10,6 +10,7 @@
 #ifndef XP_WIN
 #  include <unistd.h>
 #endif
+#include "mozilla/AppShutdown.h"
 #include "mozilla/ArrayUtils.h"
 #include "mozilla/BasePrincipal.h"
 #include "mozilla/CheckedInt.h"
@@ -1558,6 +1559,11 @@ void XMLHttpRequestMainThread::Open(const nsACString& aMethod,
     return;
   }
 
+  if (AppShutdown::IsInOrBeyond(ShutdownPhase::AppShutdownConfirmed)) {
+    aRv.Throw(NS_ERROR_ILLEGAL_DURING_SHUTDOWN);
+    return;
+  }
+
   // Gecko-specific
   if (!aAsync && responsibleDocument && GetOwner()) {
     // We have no extant document during unload, so the above general