Revert of Break peerconnection_jni.cc into multiple files, in "pc" directory.

webrtc/sdk/android/src/jni/pc/rtpreceiverobserver_jni.h

-/*
- *  Copyright 2017 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.
- */
-
-#ifndef WEBRTC_SDK_ANDROID_SRC_JNI_PC_RTPRECEIVEROBSERVER_JNI_H_
-#define WEBRTC_SDK_ANDROID_SRC_JNI_PC_RTPRECEIVEROBSERVER_JNI_H_
-
-#include "webrtc/api/rtpreceiverinterface.h"
-#include "webrtc/sdk/android/src/jni/jni_helpers.h"
-
-namespace webrtc_jni {
-
-// Adapter between the C++ RtpReceiverObserverInterface and the Java
-// RtpReceiver.Observer interface. Wraps an instance of the Java interface and
-// dispatches C++ callbacks to Java.
-class RtpReceiverObserverJni : public webrtc::RtpReceiverObserverInterface {
- public:
-  RtpReceiverObserverJni(JNIEnv* jni, jobject j_observer)
-      : j_observer_global_(jni, j_observer) {}
-
-  ~RtpReceiverObserverJni() override {}
-
-  void OnFirstPacketReceived(cricket::MediaType media_type) override;
-
- private:
-  const ScopedGlobalRef<jobject> j_observer_global_;
-};
-
-}  // namespace webrtc_jni
-
-#endif  // WEBRTC_SDK_ANDROID_SRC_JNI_PC_RTPRECEIVEROBSERVER_JNI_H_