update ChangeLog
update ChangeLog

Change-Id: I05b9ac2cf8fdd26e3f2e68780dca3e613bc2f732

webmproject/libwebp,webmproject/libwebp,PKRoma/libwebp,PKRoma/libwebp,webmproject/libwebp,PKRoma/libwebp,PKRoma/libwebp,PKRoma/libwebp,webmproject/libwebp,webmproject/libwebp,PKRoma/libwebp