Add version-specific defines for each C interface.

ppapi/c/ppb_audio_config.h

 /* Copyright (c) 2011 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_PPB_AUDIO_CONFIG_H_
 #define PPAPI_C_PPB_AUDIO_CONFIG_H_
 
 #include "ppapi/c/pp_bool.h"
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/c/pp_macros.h"
 #include "ppapi/c/pp_resource.h"
 #include "ppapi/c/pp_stdint.h"
 
-#define PPB_AUDIO_CONFIG_INTERFACE "PPB_AudioConfig;0.5"
+#define PPB_AUDIO_CONFIG_INTERFACE_0_5 "PPB_AudioConfig;0.5"
+#define PPB_AUDIO_CONFIG_INTERFACE PPB_AUDIO_CONFIG_INTERFACE_0_5
 
 /**
  * @file
  * This file defines the PPB_AudioConfig interface for establishing an
  * audio configuration resource within the browser. Refer to the
  * <a href="/chrome/nativeclient/docs/audio.html">Pepper Audio API Code
  * Walkthrough</a> for information on using this interface.
  */
 
 /**
@@ skipping 136 matching lines @@
    * more on sample frame counts.
    */
   uint32_t (*GetSampleFrameCount)(PP_Resource config);
 };
 /**
  * @}
  */
 
 #endif  /* PPAPI_C_PPB_AUDIO_CONFIG_H_ */