Android: Add common function for adding/releasing native reference

webrtc/sdk/android/src/jni/pc/peerconnection_jni.cc

 /*
  *  Copyright 2013 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 40 matching lines @@
     JNIEnv* jni,
     jobject j_pc) {
   jfieldID native_pc_id =
       GetFieldID(jni, GetObjectClass(jni, j_pc), "nativePeerConnection", "J");
   jlong j_p = GetLongField(jni, j_pc, native_pc_id);
   return rtc::scoped_refptr<webrtc::PeerConnectionInterface>(
       reinterpret_cast<webrtc::PeerConnectionInterface*>(j_p));
 }
 
 JNI_FUNCTION_DECLARATION(void,
-                         PeerConnection_freePeerConnection,
-                         JNIEnv*,
-                         jclass,
-                         jlong j_p) {
-  reinterpret_cast<webrtc::PeerConnectionInterface*>(j_p)->Release();
-}
-
-JNI_FUNCTION_DECLARATION(void,
                          PeerConnection_freeObserver,
                          JNIEnv*,
                          jclass,
                          jlong j_p) {
   PeerConnectionObserverJni* p =
       reinterpret_cast<PeerConnectionObserverJni*>(j_p);
   delete p;
 }
 
 JNI_FUNCTION_DECLARATION(jobject,
@@ skipping 346 matching lines @@
 
 JNI_FUNCTION_DECLARATION(void,
                          PeerConnection_close,
                          JNIEnv* jni,
                          jobject j_pc) {
   ExtractNativePC(jni, j_pc)->Close();
   return;
 }
 
 }  // namespace webrtc_jni