Back out changeset d5d3bf67dd1b (bug 1221852) for Android and B2G emulator and Mulet timeouts in test_sharedWorker_ports.html

CLOSED TREE

dom/workers/SharedWorker.cpp

@@ -136,6 +136,7 @@ SharedWorker::Close()
 
   if (mMessagePort) {
     mMessagePort->Close();
+    mMessagePort = nullptr;
   }
 }