Android: Replace webrtc_jni namespace with nested jni namespace

webrtc/sdk/android/src/jni/pc/datachannelobserver_jni.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/pc/datachannelobserver_jni.h"
 
 #include "webrtc/sdk/android/src/jni/classreferenceholder.h"
 
-namespace webrtc_jni {
+namespace webrtc {
+namespace jni {
 
 // Convenience, used since callbacks occur on the signaling thread, which may
 // be a non-Java thread.
 static JNIEnv* jni() {
   return AttachCurrentThreadIfNeeded();
 }
 
 DataChannelObserverJni::DataChannelObserverJni(JNIEnv* jni, jobject j_observer)
     : j_observer_global_(jni, j_observer),
       j_observer_class_(jni, GetObjectClass(jni, j_observer)),
@@ skipping 19 matching lines @@
                         previous_amount);
   CHECK_EXCEPTION(jni()) << "error during CallVoidMethod";
 }
 
 void DataChannelObserverJni::OnStateChange() {
   ScopedLocalRefFrame local_ref_frame(jni());
   jni()->CallVoidMethod(*j_observer_global_, j_on_state_change_mid_);
   CHECK_EXCEPTION(jni()) << "error during CallVoidMethod";
 }
 
-void DataChannelObserverJni::OnMessage(const webrtc::DataBuffer& buffer) {
+void DataChannelObserverJni::OnMessage(const DataBuffer& buffer) {
   ScopedLocalRefFrame local_ref_frame(jni());
   jobject byte_buffer = jni()->NewDirectByteBuffer(
       const_cast<char*>(buffer.data.data<char>()), buffer.data.size());
   jobject j_buffer = jni()->NewObject(*j_buffer_class_, j_buffer_ctor_,
                                       byte_buffer, buffer.binary);
   jni()->CallVoidMethod(*j_observer_global_, j_on_message_mid_, j_buffer);
   CHECK_EXCEPTION(jni()) << "error during CallVoidMethod";
 }
 
-}  // namespace webrtc_jni
+}  // namespace jni
+}  // namespace webrtc