Android: Replace webrtc_jni namespace with nested jni namespace

webrtc/examples/unityplugin/classreferenceholder.h

Index: webrtc/examples/unityplugin/classreferenceholder.h
diff --git a/webrtc/examples/unityplugin/classreferenceholder.h b/webrtc/examples/unityplugin/classreferenceholder.h
index a3f83e8a23f9c1751de17bed5cf52635e0b5e290..7d9a71bbb4a0e71d0f3a5e531707adfb0fc3f7fc 100644
--- a/webrtc/examples/unityplugin/classreferenceholder.h
+++ b/webrtc/examples/unityplugin/classreferenceholder.h
@@ -8,7 +8,7 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-// This is a supplement of webrtc_jni::ClassReferenceHolder.
+// This is a supplement of webrtc::jni::ClassReferenceHolder.
 // The purpose of this ClassReferenceHolder is to load the example
 // specific java class into JNI c++ side, so that our c++ code can
 // call those java functions.