Add version-specific defines for each C interface.

ppapi/c/ppb_url_loader.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_URL_LOADER_H_
 #define PPAPI_C_PPB_URL_LOADER_H_
 
 #include "ppapi/c/pp_bool.h"
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/c/pp_resource.h"
 #include "ppapi/c/pp_stdint.h"
 
 struct PP_CompletionCallback;
 
-#define PPB_URLLOADER_INTERFACE "PPB_URLLoader;0.1"
+#define PPB_URLLOADER_INTERFACE_0_1 "PPB_URLLoader;0.1"
+#define PPB_URLLOADER_INTERFACE PPB_URLLOADER_INTERFACE_0_1
 
 /**
  * @file
  * This file defines the PPB_URLLoader interface for loading URLs.
  */
 
 /**
  * @addtogroup Interfaces
  * @{
  */
@@ skipping 169 matching lines @@
    * @param[in] loader A PP_Resource corresponding to a URLLoader.
    */
   void (*Close)(PP_Resource loader);
 };
 /**
  * @}
  */
 
 #endif  /* PPAPI_C_PPB_URL_LOADER_H_ */