Started on Resource class.

src/shared/ppapi_proxy/plugin_audio_config.cc

Index: src/shared/ppapi_proxy/plugin_audio_config.cc
diff --git a/src/shared/ppapi_proxy/plugin_audio_config.cc b/src/shared/ppapi_proxy/plugin_audio_config.cc
index f441f5aad3839ced9b97e8aa9a6c1137ecbe94a9..40900d323b930c1c9afd899db36b808ca28a53a5 100644
--- a/src/shared/ppapi_proxy/plugin_audio_config.cc
+++ b/src/shared/ppapi_proxy/plugin_audio_config.cc
@@ -32,9 +32,9 @@ uint32_t RecommendSampleFrameCount(uint32_t request_sample_frame_count) {
   return 0;
 }
 
-PP_Bool IsAudioConfig(PP_Resource config) {
-  UNREFERENCED_PARAMETER(config);
-  return PP_FALSE;
+PP_Bool IsAudioConfig(PP_Resource resource) {
+  return PluginResource::GetAs<PluginAudioConfig>(resource).get()
+      ? PP_TRUE : PP_FALSE;
 }
 
 PP_AudioSampleRate_Dev GetSampleRate(PP_Resource config) {