Add version-specific defines for each C interface.

ppapi/c/ppb_url_response_info.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_RESPONSE_INFO_H_
 #define PPAPI_C_PPB_URL_RESPONSE_INFO_H_
 
 #include "ppapi/c/pp_bool.h"
 #include "ppapi/c/pp_macros.h"
 #include "ppapi/c/pp_resource.h"
@@ skipping 34 matching lines @@
   PP_URLRESPONSEPROPERTY_STATUSLINE,
 
   /** This corresponds to a string(PP_VARTYPE_STRING), \n delimited */
   PP_URLRESPONSEPROPERTY_HEADERS
 } PP_URLResponseProperty;
 PP_COMPILE_ASSERT_SIZE_IN_BYTES(PP_URLResponseProperty, 4);
 /**
  * @}
  */
 
-#define PPB_URLRESPONSEINFO_INTERFACE "PPB_URLResponseInfo;0.1"
+#define PPB_URLRESPONSEINFO_INTERFACE_0_1 "PPB_URLResponseInfo;0.1"
+#define PPB_URLRESPONSEINFO_INTERFACE PPB_URLRESPONSEINFO_INTERFACE_0_1
 
 /**
  *
  * @addtogroup Interfaces
  * @{
  */
 
 /**
  * The PPB_URLResponseInfo interface contains pointers to functions for
  * examining URL responses. Refer to PPB_URLLoader for further
@@ skipping 38 matching lines @@
    * has not been opened yet.
    */
   PP_Resource (*GetBodyAsFileRef)(PP_Resource response);
 };
 /**
  * @}
  */
 
 #endif  /* PPAPI_C_PPB_URL_RESPONSE_INFO_H_ */