Make a new test to enforce the sizes of all structs and enums in the C API....

ppapi/c/dev/ppb_file_io_dev.h

 // 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_FILE_IO_DEV_H_
 #define PPAPI_C_DEV_PPB_FILE_IO_DEV_H_
 
 #include "ppapi/c/pp_bool.h"
 #include "ppapi/c/pp_module.h"
 #include "ppapi/c/pp_resource.h"
@@ skipping 18 matching lines @@
 
   // Requests that the file be truncated to length 0 if it exists and is a
   // regular file.  PP_FILEOPENFLAG_WRITE must also be specified.
   PP_FILEOPENFLAG_TRUNCATE  = 1 << 3,
 
   // Requests that the file is created when this flag is combined with
   // PP_FILEOPENFLAG_CREATE.  If this flag is specified, and the file already
   // exists, then the FileIO::Open call will fail.
   PP_FILEOPENFLAG_EXCLUSIVE = 1 << 4
 } PP_FileOpenFlags_Dev;
+PP_COMPILE_ASSERT_SIZE_IN_BYTES(PP_FileOpenFlags_Dev, 4);
 
 #define PPB_FILEIO_DEV_INTERFACE "PPB_FileIO(Dev);0.2"
 
 // Use this interface to operate on a regular file (PP_FileType_Regular).
 struct PPB_FileIO_Dev {
   // Creates a new FileIO object.  Returns 0 if the module is invalid.
   PP_Resource (*Create)(PP_Module module);
 
   // Returns PP_TRUE if the given resource is a FileIO. Returns PP_FALSE if the
   // resource is invalid or some type other than a FileIO.
@@ skipping 58 matching lines @@
   // Cancels any IO that may be pending, and closes the FileIO object.  Any
   // pending callbacks will still run, reporting PP_Error_Aborted if pending IO
   // was interrupted.  It is NOT valid to call Open again after a call to this
   // method.  Note: If the FileIO object is destroyed, and it is still open,
   // then it will be implicitly closed, so you are not required to call the
   // Close method.
   void (*Close)(PP_Resource file_io);
 };
 
 #endif  // PPAPI_C_DEV_PPB_FILE_IO_DEV_H_