Bug 208607 - reconfigure libpng for smaller imglib2.

Patch by glennrp@imagemagick.org, r+sr=tor

modules/libimg/png/MOZCHANGES

@@ -10,8 +10,10 @@ Changes made to pristine png source by mozilla.org developers.
 
 2003/07/03  -- enable PNG_NO_WRITE_SUPPORTED in mozpngconf.h (bug 208607)
 
-2003/07/29  -- Add "moz_" decoration on exported symbols (bug 181936).  Set
+2003/07/29  -- Add "MOZ_" decoration on exported symbols (bug 181936).  Set
                "PNG_NO_GLOBAL_ARRAYS" to reduce number of exported symbols.
                Remove some legacy (1.0.x) code from png.c and pngread.c
 
 2004/05/07  -- out-of-bounds read in error processing (bug 242915)
+
+2004/06/30  -- enable more PNG_NO_*_SUPPORTED in mozpngconf.h (bug 208607)

modules/libimg/png/mozpngconf.h

@@ -72,6 +72,15 @@
 
 #define PNG_NO_WRITE_SUPPORTED
 
+#define PNG_NO_READ_STRIP_ALPHA
+#define PNG_NO_USER_TRANSFORM_PTR
+#define PNG_NO_READ_oFFs
+#define PNG_NO_HANDLE_AS_UNKNOWN
+#define PNG_NO_CONSOLE_IO
+#define PNG_NO_ZALLOC_ZERO
+#define PNG_NO_ERROR_NUMBERS
+#define PNG_NO_EASY_ACCESS
+
 /* Mangle names of exported libpng functions so different libpng versions
    can coexist. It is recommended that if you do this, you give your
    library a different name such as "mozlibpng" instead of "libpng". */