Adding Java binding for CreateSender.

talk/app/webrtc/java/src/org/webrtc/PeerConnection.java

Index: talk/app/webrtc/java/src/org/webrtc/PeerConnection.java
diff --git a/talk/app/webrtc/java/src/org/webrtc/PeerConnection.java b/talk/app/webrtc/java/src/org/webrtc/PeerConnection.java
index 50023001d724b12b8da0b8d97704bd36020a6895..f235370b67915137d345c649f38b122e5eefa4b6 100644
--- a/talk/app/webrtc/java/src/org/webrtc/PeerConnection.java
+++ b/talk/app/webrtc/java/src/org/webrtc/PeerConnection.java
@@ -28,7 +28,6 @@
 
 package org.webrtc;
 
-import java.util.ArrayList;
 import java.util.Collections;
 import java.util.LinkedList;
 import java.util.List;
@@ -223,6 +222,14 @@ public class PeerConnection {
     localStreams.remove(stream);
   }
 
+  public RtpSender createSender(String kind) {

[pthatcher1, 2015/12/02 19:17:06]

Should we put a comment saying that it can return null, and what that means?

+    RtpSender new_sender = nativeCreateSender(kind);

[pthatcher1, 2015/12/02 19:17:06]

Why not just "sender"?

+    if (new_sender != null) {
+      senders.add(new_sender);
+    }
+    return new_sender;
+  }
+
   // Note that calling getSenders will dispose of the senders previously
   // returned (and same goes for getReceivers).
   public List<RtpSender> getSenders() {
@@ -288,6 +295,8 @@ public class PeerConnection {
   private native boolean nativeGetStats(
       StatsObserver observer, long nativeTrack);
 
+  private native RtpSender nativeCreateSender(String kind);
+
   private native List<RtpSender> nativeGetSenders();
 
   private native List<RtpReceiver> nativeGetReceivers();