Add version-specific defines for each C interface.

ppapi/c/dev/ppb_graphics_3d_dev.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_DEV_PPB_GRAPHICS_3D_DEV_H_
 #define PPAPI_C_DEV_PPB_GRAPHICS_3D_DEV_H_
 
 #include "ppapi/c/dev/pp_graphics_3d_dev.h"
 
 #include "ppapi/c/pp_bool.h"
@@ skipping 13 matching lines @@
 // context = g3d->Create(instance, config, attribs, &context);
 // inst->BindGraphics(instance, context);
 //
 // // Present one frame.
 // gles2->Clear(context, GL_COLOR_BUFFER);
 // g3d->SwapBuffers(context);
 //
 // // Shutdown.
 // core->ReleaseResource(context);
 
-#define PPB_GRAPHICS_3D_DEV_INTERFACE "PPB_Graphics3D(Dev);0.4"
+#define PPB_GRAPHICS_3D_DEV_INTERFACE_0_4 "PPB_Graphics3D(Dev);0.4"
+#define PPB_GRAPHICS_3D_DEV_INTERFACE PPB_GRAPHICS_3D_DEV_INTERFACE_0_4
 
 struct PPB_Graphics3D_Dev {
   // TODO(alokp): Do these functions need module argument?
 
   // Retrieves the list of all available PP_Config3D_Devs.
   // configs is a pointer to a buffer containing config_size elements.
   // On success, PP_OK is returned. The number of configurations is returned
   // in num_config, and elements 0 through num_config - 1 of configs are filled
   // in with valid PP_Config3D_Devs. No more than config_size
   // PP_Config3D_Devs will be returned even if more are available.
@@ skipping 174 matching lines @@
   // plugin's current state is actually on the screen, this function provides a
   // way to rate limit animations. By waiting until the image is on the screen
   // before painting the next frame, you can ensure you're not generating
   // updates faster than the screen can be updated.
   int32_t (*SwapBuffers)(PP_Resource context,
                          struct PP_CompletionCallback callback);
 };
 
 #endif  /* PPAPI_C_DEV_PPB_GRAPHICS_3D_DEV_H_ */