Change MediatorThreadImpl::Run to process messages forever and periodically call PumpAuxiliaryLoops to run the 3 (!!:(!!) other loops associated with this thread. There was previously a race where

quit would be called and set a cancellation flag before the posted task would 
get executed.

BUG=37771

Review URL: http://codereview.chromium.org/984001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@41724 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 38 insertions, 17 deletions

diff --git a/chrome/browser/sync/engine/syncapi.cc b/chrome/browser/sync/engine/syncapi.cc
index 23243d5..a149a08 100644
--- a/chrome/browser/sync/engine/syncapi.cc
+++ b/chrome/browser/sync/engine/syncapi.cc
@@ -1485,11 +1485,13 @@ void SyncManager::SyncInternal::Shutdown() {
   }
 
   // Shutdown the xmpp buzz connection.
-  LOG(INFO) << "P2P: Mediator logout started.";
   if (talk_mediator()) {
+    LOG(INFO) << "P2P: Mediator logout started.";
     talk_mediator()->Logout();
+    LOG(INFO) << "P2P: Mediator logout completed.";
+    talk_mediator_.reset();
+    LOG(INFO) << "P2P: Mediator destroyed.";
   }
-  LOG(INFO) << "P2P: Mediator logout completed.";
 
   if (dir_manager()) {
     dir_manager()->FinalSaveChangesForAll();
diff --git a/chrome/browser/sync/notifier/listener/mediator_thread_impl.cc b/chrome/browser/sync/notifier/listener/mediator_thread_impl.cc
index a6df235..11cf90a 100644
--- a/chrome/browser/sync/notifier/listener/mediator_thread_impl.cc
+++ b/chrome/browser/sync/notifier/listener/mediator_thread_impl.cc
@@ -59,20 +59,8 @@ void MediatorThreadImpl::Run() {
   socket_server->WakeUp();
 #endif
 
-  do {
-#if defined(OS_WIN)
-    ::MSG message;
-    if (::PeekMessage(&message, NULL, 0, 0, PM_REMOVE)) {
-      ::TranslateMessage(&message);
-      ::DispatchMessage(&message);
-    }
-#endif
-    ProcessMessages(100);
-    if (pump_.get() && pump_->HasPendingTimeoutTask()) {
-      pump_->WakeTasks();
-    }
-    MessageLoop::current()->RunAllPending();
-  } while (!IsQuitting());
+  Post(this, CMD_PUMP_AUXILIARY_LOOPS);
+  ProcessMessages(talk_base::kForever);
 
 #if defined(OS_WIN)
   set_socketserver(old_socket_server);
@@ -80,11 +68,36 @@ void MediatorThreadImpl::Run() {
 #endif
 }
 
+void MediatorThreadImpl::PumpAuxiliaryLoops() {
+#if defined(OS_WIN)
+  ::MSG message;
+  if (::PeekMessage(&message, NULL, 0, 0, PM_REMOVE)) {
+    ::TranslateMessage(&message);
+    ::DispatchMessage(&message);
+  }
+#endif
+  if (pump_.get() && pump_->HasPendingTimeoutTask()) {
+    pump_->WakeTasks();
+  }
+  MessageLoop::current()->RunAllPending();
+  // We want to pump auxiliary loops every 100ms until this thread is stopped,
+  // at which point this call will do nothing.
+  PostDelayed(100, this, CMD_PUMP_AUXILIARY_LOOPS);
+}
+
 void MediatorThreadImpl::Login(const buzz::XmppClientSettings& settings) {
   Post(this, CMD_LOGIN, new LoginData(settings));
 }
 
+void MediatorThreadImpl::Stop() {
+  Thread::Stop();
+  CHECK(!login_.get() && !pump_.get()) << "Logout should be called prior to"
+      << "message queue exit.";
+}
+
 void MediatorThreadImpl::Logout() {
+  CHECK(!IsQuitting())
+      << "Logout should be called prior to message queue exit.";
   Post(this, CMD_DISCONNECT);
   Stop();
 }
@@ -125,6 +138,9 @@ void MediatorThreadImpl::OnMessage(talk_base::Message* msg) {
     case CMD_SUBSCRIBE_FOR_UPDATES:
       DoSubscribeForUpdates();
       break;
+    case CMD_PUMP_AUXILIARY_LOOPS:
+      PumpAuxiliaryLoops();
+      break;
     default:
       LOG(ERROR) << "P2P: Someone passed a bad message to the thread.";
       break;
diff --git a/chrome/browser/sync/notifier/listener/mediator_thread_impl.h b/chrome/browser/sync/notifier/listener/mediator_thread_impl.h
index f8cf359..08b07cd 100644
--- a/chrome/browser/sync/notifier/listener/mediator_thread_impl.h
+++ b/chrome/browser/sync/notifier/listener/mediator_thread_impl.h
@@ -48,7 +48,8 @@ enum MEDIATOR_CMD {
   CMD_DISCONNECT,
   CMD_LISTEN_FOR_UPDATES,
   CMD_SEND_NOTIFICATION,
-  CMD_SUBSCRIBE_FOR_UPDATES
+  CMD_SUBSCRIBE_FOR_UPDATES,
+  CMD_PUMP_AUXILIARY_LOOPS,
 };
 
 // Used to pass authentication information from the mediator to the thread.
@@ -73,6 +74,7 @@ class MediatorThreadImpl
 
   // Start the thread.
   virtual void Start();
+  virtual void Stop();
   virtual void Run();
 
   // These are called from outside threads, by the talk mediator object.
@@ -94,6 +96,7 @@ class MediatorThreadImpl
   void DoListenForUpdates();
   void DoSendNotification();
   void DoStanzaLogging();
+  void PumpAuxiliaryLoops();
 
   // These handle messages indicating an event happened in the outside world.
   void OnUpdateListenerMessage();