[Sync] Fix race condition in P2PNotifier with sending notifications

jingle/notifier/listener/mediator_thread_impl.h

Index: jingle/notifier/listener/mediator_thread_impl.h
diff --git a/jingle/notifier/listener/mediator_thread_impl.h b/jingle/notifier/listener/mediator_thread_impl.h
index 4015a81f64a4d9c4539c637f4dfffd838a8a3d6c..06567578fc3bc315175bf70724eec661da2a654a 100644
--- a/jingle/notifier/listener/mediator_thread_impl.h
+++ b/jingle/notifier/listener/mediator_thread_impl.h
@@ -25,6 +25,7 @@
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
 #include "base/task.h"
 #include "jingle/notifier/base/notifier_options.h"
 #include "jingle/notifier/listener/mediator_thread.h"
@@ -37,6 +38,10 @@ namespace buzz {
 class XmppClientSettings;
 }  // namespace buzz
 
+namespace talk_base {
+class Task;
+}  // namespace talk_base
+
 namespace notifier {
 
 class MediatorThreadImpl : public MediatorThread {
@@ -59,6 +64,11 @@ class MediatorThreadImpl : public MediatorThread {
   virtual void SendNotification(const Notification& data);
   virtual void UpdateXmppSettings(const buzz::XmppClientSettings& settings);
 
+  // Used by unit tests.  Make sure that tests that use this have the
+  // IO message loop proxy passed in via |notifier_options| pointing
+  // to the current thread.
+  void TriggerOnConnectForTest(base::WeakPtr<talk_base::Task> base_task);
+
  private:
   void CheckOrSetValidThread();
   // The logic of Logout without the thread check so it can be called in the