Bug 1481084 - Assertion OnSocketThread() in HttpBackgroundChannelChild::RecvOnStopRequest during shutdown r=dragana

OnSocketTread doesn't work properly during shutdown because nsSocketTransportService2.cpp::gSocketThread is null.
We call gSocketTransportService->IsOnCurrentThreadInfallible() instead, just like we already do in HttpBackgroundChannelChild::ActorDestroy()

Differential Revision: https://phabricator.services.mozilla.com/D5050

--HG--
extra : moz-landing-system : lando

netwerk/protocol/http/HttpBackgroundChannelChild.cpp

@@ -181,7 +181,8 @@ HttpBackgroundChannelChild::RecvOnStopRequest(
                                     const nsHttpHeaderArray& aResponseTrailers)
 {
   LOG(("HttpBackgroundChannelChild::RecvOnStopRequest [this=%p]\n", this));
-  MOZ_ASSERT(OnSocketThread());
+  MOZ_ASSERT(gSocketTransportService);
+  MOZ_ASSERT(gSocketTransportService->IsOnCurrentThreadInfallible());
 
   // It's enough to set this from (just before) OnStopRequest notification, since
   // we don't need this value sooner than a channel was done loading - everything