Fix XmppSignalStrategy to return correct result from SendStanza().

remoting/signaling/xmpp_signal_strategy.cc

Index: remoting/signaling/xmpp_signal_strategy.cc
diff --git a/remoting/signaling/xmpp_signal_strategy.cc b/remoting/signaling/xmpp_signal_strategy.cc
index 51eae4bc62c75ac11de54e5c55b3309ec8d11867..5edbb377f5b69a30ac947e436623f1971152dad8 100644
--- a/remoting/signaling/xmpp_signal_strategy.cc
+++ b/remoting/signaling/xmpp_signal_strategy.cc
@@ -191,6 +191,7 @@ void XmppSignalStrategy::Core::Disconnect() {
     writer_.reset();
     socket_.reset();
     tls_state_ = TlsState::NOT_REQUESTED;
+    read_pending_ = false;
 
     FOR_EACH_OBSERVER(Listener, listeners_,
                       OnSignalStrategyStateChange(DISCONNECTED));
@@ -234,13 +235,15 @@ bool XmppSignalStrategy::Core::SendStanza(scoped_ptr<buzz::XmlElement> stanza) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   if (!stream_parser_) {
-    VLOG(0) << "Dropping signalling message because XMPP "
-               "connection has been terminated.";
+    VLOG(0) << "Dropping signalling message because XMPP is not connected.";
     return false;
   }
 
   SendMessage(stanza->Str());
-  return true;
+
+  // Return false if the SendMessage() call above resulted in the SignalStrategy
+  // being disconnected.
+  return stream_parser_ != nullptr;
 }
 
 void XmppSignalStrategy::Core::SetAuthInfo(const std::string& username,