Remove FFI_ from CPDFSDK_Environment method names

public/fpdf_formfill.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_FORMFILL_H_
 #define PUBLIC_FPDF_FORMFILL_H_
 
 #include "fpdfview.h"
@@ skipping 592 matching lines @@
   * Interface Version:
   *           1
   * Implementation Required:
   *           yes
   * Parameters:
   *       pThis       -   Pointer to the interface structure itself.
   *       page        -   Handle to page. Returned by FPDF_LoadPage function.
   * Return value:
   *       The page rotation. Should be 0(0 degree),1(90 degree),2(180
   * degree),3(270 degree), in a clockwise direction.
+  *
+  * Note: Unused.
   * */
   int (*FFI_GetRotation)(struct _FPDF_FORMFILLINFO* pThis, FPDF_PAGE page);
 
   /**
   * Method: FFI_ExecuteNamedAction
   *           This method will execute an named action.
   * Interface Version:
   *           1
   * Implementation Required:
   *           yes
@@ skipping 1131 matching lines @@
 FPDF_StringHandleAddString(FPDF_STRINGHANDLE stringHandle,
                            FPDF_BYTESTRING bsText,
                            FPDF_DWORD size);
 #endif  // PDF_ENABLE_XFA
 
 #ifdef __cplusplus
 }
 #endif
 
 #endif  // PUBLIC_FPDF_FORMFILL_H_