Adding a way for a Java RtpSender to set a track without taking ownership.

talk/app/webrtc/java/jni/peerconnection_jni.cc

Index: talk/app/webrtc/java/jni/peerconnection_jni.cc
diff --git a/talk/app/webrtc/java/jni/peerconnection_jni.cc b/talk/app/webrtc/java/jni/peerconnection_jni.cc
index c31859def809318b3bf61e400504dc112bce1478..475748409c5cd8439cbfb634e905b519d86c4fa6 100644
--- a/talk/app/webrtc/java/jni/peerconnection_jni.cc
+++ b/talk/app/webrtc/java/jni/peerconnection_jni.cc
@@ -2120,11 +2120,11 @@ JOW(jbyteArray, CallSessionFileRotatingLogSink_nativeGetLogData)(
   return result;
 }
 
-JOW(void, RtpSender_nativeSetTrack)(JNIEnv* jni,
+JOW(jboolean, RtpSender_nativeSetTrack)(JNIEnv* jni,
                                     jclass,
                                     jlong j_rtp_sender_pointer,
                                     jlong j_track_pointer) {
-  reinterpret_cast<RtpSenderInterface*>(j_rtp_sender_pointer)
+  return reinterpret_cast<RtpSenderInterface*>(j_rtp_sender_pointer)
       ->SetTrack(reinterpret_cast<MediaStreamTrackInterface*>(j_track_pointer));
 }