Fixing overloaded-virtual compiler warning.

webrtc/api/java/jni/peerconnection_jni.cc

Index: webrtc/api/java/jni/peerconnection_jni.cc
diff --git a/webrtc/api/java/jni/peerconnection_jni.cc b/webrtc/api/java/jni/peerconnection_jni.cc
index 091b9d33077813aa5b38c1024ade499a9531495b..0dc9b5e316540929c0c3b49eb8ae3fef7a332dc0 100644
--- a/webrtc/api/java/jni/peerconnection_jni.cc
+++ b/webrtc/api/java/jni/peerconnection_jni.cc
@@ -160,6 +160,13 @@ class ConstraintsWrapper;
 // and dispatches C++ callbacks to Java.
 class PCOJava : public PeerConnectionObserver {
  public:
+  // We need these using declarations because there are two versions of each of
+  // the below methods and we only override one of them.
+  // TODO(deadbeef): Remove once there's only one version of the methods.
+  using PeerConnectionObserver::OnAddStream;
+  using PeerConnectionObserver::OnRemoveStream;
+  using PeerConnectionObserver::OnDataChannel;
+
   PCOJava(JNIEnv* jni, jobject j_observer)
       : j_observer_global_(jni, j_observer),
         j_observer_class_(jni, GetObjectClass(jni, *j_observer_global_)),