Change ppapi C++ comment style into C.

ppapi/c/dev/ppb_audio_config_dev.h

Index: ppapi/c/dev/ppb_audio_config_dev.h
diff --git a/ppapi/c/dev/ppb_audio_config_dev.h b/ppapi/c/dev/ppb_audio_config_dev.h
index 411ad7631a395ac841b12c35b58b3c3d8ec4ca89..22f3918a778c95f4bee0d886ecf0cab60a27157d 100644
--- a/ppapi/c/dev/ppb_audio_config_dev.h
+++ b/ppapi/c/dev/ppb_audio_config_dev.h
@@ -1,7 +1,7 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
+/* Copyright (c) 2010 The Chromium Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
 #ifndef PPAPI_C_DEV_PPB_AUDIO_CONFIG_DEV_H_
 #define PPAPI_C_DEV_PPB_AUDIO_CONFIG_DEV_H_
 
@@ -93,4 +93,5 @@ struct PPB_AudioConfig_Dev {
   uint32_t (*GetSampleFrameCount)(PP_Resource config);
 };
 
-#endif  // PPAPI_C_DEV_PPB_AUDIO_CONFIG_DEV_H_
+#endif  /* PPAPI_C_DEV_PPB_AUDIO_CONFIG_DEV_H_ */
+