bug 374810 pick up crash fix from libpng 1.2.17, patch=glennrp, r=tor, sr=dveditz

configure.in

@@ -103,7 +103,7 @@ _SUBDIR_CONFIG_ARGS="$ac_configure_args"
 dnl Set the version number of the libs included with mozilla
 dnl ========================================================
 MOZJPEG=62
-MOZPNG=10207
+MOZPNG=10217
 MOZZLIB=0x1230
 NSPR_VERSION=4
 NSS_VERSION=3

modules/libimg/png/MOZCHANGES

@@ -1,6 +1,10 @@
 
 Changes made to pristine png source by mozilla.org developers.
 
+2007/05/05  -- Zero png_ptr->num_trans on CRC error (bug 374810)
+
+2007/04/19  -- Synced with libpng-1.2.16 tree
+
 2007/03/20  -- Added support for APNG
 
 2006/06/27  -- Synced with libpng-1.2.12 tree

modules/libimg/png/pngrutil.c

@@ -1319,7 +1319,10 @@ png_handle_tRNS(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    }
 
    if (png_crc_finish(png_ptr, 0))
+   {
+      png_ptr->num_trans = 0;
       return;
+   }
 
    png_set_tRNS(png_ptr, info_ptr, readbuf, png_ptr->num_trans,
       &(png_ptr->trans_values));