Bug 1786881 - Reuse connection for connection based auth, r=necko-reviewers,valentin

Differential Revision: https://phabricator.services.mozilla.com/D156154

netwerk/protocol/http/nsHttpConnection.cpp

@@ -1000,7 +1000,6 @@ void nsHttpConnection::HandleTunnelResponse(uint16_t responseStatus,
     LOG(("proxy CONNECT failed! endtoendssl=%d onlyconnect=%d\n", isHttps,
          onlyConnect));
     mTransaction->SetProxyConnectFailed();
-    mDontReuse = true;
   }
 }