Relanding: Break peerconnection_jni.cc into multiple files, in "pc" directory.

webrtc/sdk/android/src/jni/null_video_jni.cc

-/*
- *  Copyright (c) 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.
- */
-
-#include "webrtc/sdk/android/src/jni/video_jni.h"
-
-namespace webrtc_jni {
-
-cricket::WebRtcVideoEncoderFactory* CreateVideoEncoderFactory(
-    JNIEnv* jni,
-    jobject j_encoder_factory) {
-  return nullptr;
-}
-
-cricket::WebRtcVideoDecoderFactory* CreateVideoDecoderFactory(
-    JNIEnv* jni,
-    jobject j_decoder_factory) {
-  return nullptr;
-}
-
-jobject GetJavaSurfaceTextureHelper(
-    const rtc::scoped_refptr<SurfaceTextureHelper>& surface_texture_helper) {
-  return nullptr;
-}
-
-}  // namespace webrtc_jni