XFA: Remove ifdefs for _FX_MANAGED_CODE_.

third_party/lpng_v163/pngmem.c

 /* pngmem.c - stub functions for memory allocation
  *
  * Last changed in libpng 1.6.0 [February 14, 2013]
  * Copyright (c) 1998-2013 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
  *
  * This file provides a location for all memory allocation.  Users who
  * need special memory handling are expected to supply replacement
  * functions for png_malloc() and png_free(), and to use
  * png_create_read_struct_2() and png_create_write_struct_2() to
  * identify the replacement functions.
  */
 
 #include "pngpriv.h"
 
-#if defined(_FX_MANAGED_CODE_) && defined(__cplusplus)
-extern "C" {
-#endif
-
 void*   FXMEM_DefaultAlloc(int byte_size, int);
 void    FXMEM_DefaultFree(void* pointer, int);
 
-#if defined(_FX_MANAGED_CODE_) && defined(__cplusplus)
-}
-#endif
-
 #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
 /* Free a png_struct */
 void /* PRIVATE */
 png_destroy_png_struct(png_structrp png_ptr)
 {
    if (png_ptr != NULL)
    {
       /* png_free might call png_error and may certainly call
        * png_get_mem_ptr, so fake a temporary png_struct to support this.
        */
@@ skipping 238 matching lines @@
 png_voidp PNGAPI
 png_get_mem_ptr(png_const_structrp png_ptr)
 {
    if (png_ptr == NULL)
       return NULL;
 
    return png_ptr->mem_ptr;
 }
 #endif /* PNG_USER_MEM_SUPPORTED */
 #endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */