PPAPI: Make blocking completion callbacks work.

ppapi/shared_impl/ppb_audio_config_shared.cc

Index: ppapi/shared_impl/ppb_audio_config_shared.cc
diff --git a/ppapi/shared_impl/ppb_audio_config_shared.cc b/ppapi/shared_impl/ppb_audio_config_shared.cc
index a88b851e3e6c3fa6f50f6f5f3ea8ab2dd5732a85..6660166a6de1b9be0749ae22a6ff496377e7ed4e 100644
--- a/ppapi/shared_impl/ppb_audio_config_shared.cc
+++ b/ppapi/shared_impl/ppb_audio_config_shared.cc
@@ -49,7 +49,7 @@ uint32_t PPB_AudioConfig_Shared::RecommendSampleFrameCount_1_1(
     uint32_t sample_frame_count) {
   // Version 1.1: Query the back-end hardware for sample rate and buffer size,
   // and recommend a best fit based on request.
-  thunk::EnterInstance enter(instance);
+  thunk::EnterInstanceNoLock enter(instance);
   if (enter.failed())
     return 0;
 
@@ -91,7 +91,7 @@ uint32_t PPB_AudioConfig_Shared::RecommendSampleFrameCount_1_1(
 // static
 PP_AudioSampleRate PPB_AudioConfig_Shared::RecommendSampleRate(
     PP_Instance instance) {
-  thunk::EnterInstance enter(instance);
+  thunk::EnterInstanceNoLock enter(instance);
   if (enter.failed())
     return PP_AUDIOSAMPLERATE_NONE;
   PP_AudioSampleRate hardware_sample_rate = static_cast<PP_AudioSampleRate>(