Make XFA public more closely match master.

public/fpdf_flatten.h

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #ifndef PUBLIC_FPDF_FLATTEN_H_
 #define PUBLIC_FPDF_FLATTEN_H_
 
 #include "fpdfview.h"
@@ skipping 17 matching lines @@
 // Parameters:
 //          page  - Handle to the page, as returned by FPDF_LoadPage().
 //          nFlag - Intended use of the flattened result: 0 for normal display,
 //          1 for printing.
 // Return value:
 //          Either FLATTEN_FAIL, FLATTEN_SUCCESS, or FLATTEN_NOTHINGTODO (see
 //          above).
 // Comments:
 //          Currently, all failures return FLATTEN_FAIL, with no indication for
 //          the reason
-//          for the failure. The method does not support flattening any dynamic
-//          XFA fields.
+//          for the failure.
 DLLEXPORT int STDCALL FPDFPage_Flatten(FPDF_PAGE page, int nFlag);
 
 #ifdef __cplusplus
 }
 #endif
 
 #endif  // PUBLIC_FPDF_FLATTEN_H_