Add PeerConnection IsClosed check.

webrtc/api/webrtcsession_unittest.cc

Index: webrtc/api/webrtcsession_unittest.cc
diff --git a/webrtc/api/webrtcsession_unittest.cc b/webrtc/api/webrtcsession_unittest.cc
index e8234d7c1b9295ad8428b6d17fd4203e865c6c50..50ce8a8b4b6c7970fe3e99f50ec0403ce0b1974f 100644
--- a/webrtc/api/webrtcsession_unittest.cc
+++ b/webrtc/api/webrtcsession_unittest.cc
@@ -217,12 +217,14 @@ class WebRtcSessionForTest : public webrtc::WebRtcSession {
                        rtc::Thread* worker_thread,
                        rtc::Thread* signaling_thread,
                        cricket::PortAllocator* port_allocator,
-                       webrtc::IceObserver* ice_observer)
+                       webrtc::IceObserver* ice_observer,
+                       cricket::TransportController* transport_controller)
       : WebRtcSession(media_controller,
                       network_thread,
                       worker_thread,
                       signaling_thread,
-                      port_allocator) {
+                      port_allocator,
+                      transport_controller) {
     RegisterIceObserver(ice_observer);
   }
   virtual ~WebRtcSessionForTest() {}
@@ -386,7 +388,9 @@ class WebRtcSessionTest
     ASSERT_TRUE(session_.get() == NULL);
     session_.reset(new WebRtcSessionForTest(
         media_controller_.get(), rtc::Thread::Current(), rtc::Thread::Current(),
-        rtc::Thread::Current(), allocator_.get(), &observer_));
+        rtc::Thread::Current(), allocator_.get(), &observer_,
+        new cricket::TransportController(
+            rtc::Thread::Current(), rtc::Thread::Current(), allocator_.get())));
     session_->SignalDataChannelOpenMessage.connect(
         this, &WebRtcSessionTest::OnDataChannelOpenMessage);
     session_->GetOnDestroyedSignal()->connect(