git: openjdk/jdk8u: 8372534: Update Libpng to 1.6.51

[Andrew John Hughes]

Changeset: 976d0a19
Branch: master
Author:    Andrew John Hughes <andrew at openjdk.org>
Date:      2026-01-08 21:54:36 +0000
URL:       https://git.openjdk.org/jdk8u/commit/976d0a196ce036c40147535209b80143e021c2fe

8372534: Update Libpng to 1.6.51
8316030: Update Libpng to 1.6.40
8329004: Update Libpng to 1.6.43
8348598: Update Libpng to 1.6.47

Reviewed-by: abakhtin, serb
Backport-of: be7966c633830516c703f14610e4fef1bbe7f57d

! THIRD_PARTY_README
! jdk/src/share/native/sun/awt/libpng/CHANGES
! jdk/src/share/native/sun/awt/libpng/LICENSE
! jdk/src/share/native/sun/awt/libpng/README
+ jdk/src/share/native/sun/awt/libpng/UPDATING.txt
! jdk/src/share/native/sun/awt/libpng/png.c
! jdk/src/share/native/sun/awt/libpng/png.h
! jdk/src/share/native/sun/awt/libpng/pngconf.h
! jdk/src/share/native/sun/awt/libpng/pngdebug.h
! jdk/src/share/native/sun/awt/libpng/pngerror.c
! jdk/src/share/native/sun/awt/libpng/pngget.c
! jdk/src/share/native/sun/awt/libpng/pnginfo.h
! jdk/src/share/native/sun/awt/libpng/pnglibconf.h
! jdk/src/share/native/sun/awt/libpng/pngmem.c
! jdk/src/share/native/sun/awt/libpng/pngpread.c
! jdk/src/share/native/sun/awt/libpng/pngpriv.h
! jdk/src/share/native/sun/awt/libpng/pngread.c
! jdk/src/share/native/sun/awt/libpng/pngrio.c
! jdk/src/share/native/sun/awt/libpng/pngrtran.c
! jdk/src/share/native/sun/awt/libpng/pngrutil.c
! jdk/src/share/native/sun/awt/libpng/pngset.c
! jdk/src/share/native/sun/awt/libpng/pngstruct.h
! jdk/src/share/native/sun/awt/libpng/pngtrans.c