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

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

 /*
  *  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.
  */
 
-#include "webrtc/sdk/android/src/jni/rtcstatscollectorcallbackwrapper.h"
+#include "webrtc/sdk/android/src/jni/pc/rtcstatscollectorcallbackwrapper.h"
 
 #include <string>
 #include <vector>
 
 #include "webrtc/sdk/android/src/jni/classreferenceholder.h"
 
 namespace webrtc_jni {
 
 RTCStatsCollectorCallbackWrapper::RTCStatsCollectorCallbackWrapper(
     JNIEnv* jni,
@@ skipping 236 matching lines @@
         CHECK_EXCEPTION(jni) << "error during SetObjectArrayElement";
       }
       return j_values;
     }
   }
   RTC_NOTREACHED();
   return nullptr;
 }
 
 }  // namespace webrtc_jni