third_party/libpng: update to 1.2.54

third_party/libpng/pngconf.h

Index: third_party/libpng/pngconf.h
diff --git a/third_party/libpng/pngconf.h b/third_party/libpng/pngconf.h
index 008142e4dda1684d9e038d82b7f81e34aebb25f0..3d1be6b842dfe377dbe117f2e23b800e3173674a 100644
--- a/third_party/libpng/pngconf.h
+++ b/third_party/libpng/pngconf.h
@@ -1,17 +1,17 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng version 1.2.52 - November 20, 2014
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * libpng version 1.2.54, November 12, 2015
+ *
+ * Copyright (c) 1998-2015 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
- */
-
-/* Any machine specific code is near the front of this file, so if you
+ *
+ * Any machine specific code is near the front of this file, so if you
  * are configuring libpng for a machine, you may want to read the section
  * starting here down to where it starts to typedef png_color, png_text,
  * and png_info.
@@ -885,7 +885,7 @@
 
 /* Added at libpng-1.2.43 */
 #ifndef PNG_USER_CHUNK_MALLOC_MAX
-#  define PNG_USER_CHUNK_MALLOC_MAX 0
+#  define PNG_USER_CHUNK_MALLOC_MAX 8000000
 #endif
 
 #ifndef PNG_LITERAL_SHARP