PeerConnection shutdown-time fixes

- TCPPort::~TCPPort() was leaking incoming_ sockets; now they are deleted.
- PeerConnection::RemoveStream() now removes streams even if the
  PeerConnection::IsClosed().  Previously such streams would never get removed.
- Gave MediaStreamTrackInterface a virtual destructor to ensure deletes on base
  pointers are dispatched virtually.
- VideoTrack.dispose() delegates to super.dispose() (instead of leaking)
- PeerConnection.dispose() now removes streams before disposing of them.
- MediaStream.dispose() now removes tracks before disposing of them.
- VideoCapturer.dispose() only unowned VideoCapturers (mirroring C++ API)
- AppRTCDemo.disconnectAndExit() now correctly .dispose()s its
  VideoSource and PeerConnectionFactory.
- CHECK that Release()d objects are deleted when expected to (i.e. no ref-cycles
  or missing .dispose() calls) in the Java API.
- Create & Return webrtc::Traces at factory birth/death to be able to assert
  that _all_ threads started during the test are collected by the end.
- Name threads attached to the JVM more informatively for debugging.
- Removed a bunch of unnecessary scoped_refptr instances in
  peerconnection_jni.cc whose only job was messing with refcounts.

RISK=P2
TESTED=AppRTCDemo can be ended and restarted just fine instead of crashing on camera unavailability.  No more post-app-exit logcat lines.  PCTest.java now asserts that all threads are collected before exit.

BUG=2183
R=wu@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/2005004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@4534 4adac7df-926f-26a2-2b94-8c16560cd09d

talk/examples/android/src/org/appspot/apprtc/AppRTCDemoActivity.java

@@ -71,6 +71,8 @@ import java.util.List;
 public class AppRTCDemoActivity extends Activity
     implements AppRTCClient.IceServersObserver {
   private static final String TAG = "AppRTCDemoActivity";
+  private PeerConnectionFactory factory;
+  private VideoSource videoSource;
   private PeerConnection pc;
   private final PCObserver pcObserver = new PCObserver();
   private final SDPObserver sdpObserver = new SDPObserver();
@@ -183,8 +185,7 @@ public class AppRTCDemoActivity extends Activity
 
   @Override
   public void onIceServers(List<PeerConnection.IceServer> iceServers) {
-    PeerConnectionFactory factory = new PeerConnectionFactory();
-
+    factory = new PeerConnectionFactory();
     pc = factory.createPeerConnection(
         iceServers, appRtcClient.pcConstraints(), pcObserver);
 
@@ -217,7 +218,7 @@ public class AppRTCDemoActivity extends Activity
     {
       logAndToast("Creating local video source...");
       VideoCapturer capturer = getVideoCapturer();
-      VideoSource videoSource = factory.createVideoSource(
+      videoSource = factory.createVideoSource(
           capturer, appRtcClient.videoConstraints());
       MediaStream lMS = factory.createLocalMediaStream("ARDAMS");
       VideoTrack videoTrack = factory.createVideoTrack("ARDAMSv0", videoSource);
@@ -485,6 +486,14 @@ public class AppRTCDemoActivity extends Activity
         appRtcClient.disconnect();
         appRtcClient = null;
       }
+      if (videoSource != null) {
+        videoSource.dispose();
+        videoSource = null;
+      }
+      if (factory != null) {
+        factory.dispose();
+        factory = null;
+      }
       finish();
     }
   }