Added support for changing the volume of AudioTrack as discussed in BUG=webrtc:6533

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

 /*
  *  Copyright 2015 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/classreferenceholder.h"
@@ skipping 78 matching lines @@
   LoadClass(jni, "org/webrtc/RtpReceiver");
   LoadClass(jni, "org/webrtc/RtpSender");
   LoadClass(jni, "org/webrtc/SessionDescription");
   LoadClass(jni, "org/webrtc/SessionDescription$Type");
   LoadClass(jni, "org/webrtc/StatsReport");
   LoadClass(jni, "org/webrtc/StatsReport$Value");
   LoadClass(jni, "org/webrtc/SurfaceTextureHelper");
   LoadClass(jni, "org/webrtc/VideoCapturer");
   LoadClass(jni, "org/webrtc/VideoRenderer$I420Frame");
   LoadClass(jni, "org/webrtc/VideoTrack");
+  LoadClass(jni, "org/webrtc/AudioSource");

[the sun, 2017/03/17 20:31:39]

alphabetical order, please

 }
 
 ClassReferenceHolder::~ClassReferenceHolder() {
   RTC_CHECK(classes_.empty()) << "Must call FreeReferences() before dtor!";
 }
 
 void ClassReferenceHolder::FreeReferences(JNIEnv* jni) {
   for (std::map<std::string, jclass>::const_iterator it = classes_.begin();
       it != classes_.end(); ++it) {
     jni->DeleteGlobalRef(it->second);
@@ skipping 18 matching lines @@
   RTC_CHECK(inserted) << "Duplicate class name: " << name;
 }
 
 // Returns a global reference guaranteed to be valid for the lifetime of the
 // process.
 jclass FindClass(JNIEnv* jni, const char* name) {
   return g_class_reference_holder->GetClass(name);
 }
 
 }  // namespace webrtc_jni