Update gdk-pixbuf2 to 2.28.1
* Fix build with libpng 1.6
* Translation updates (Tadjik, Russian, Crimean Tatar, Hindi)
* Allow prepare_func call in stop_load (695228)
* Translation updates (Lithuanian, German, Basque, Belarusian,
Thai, Greek, Indonesian, Korean, Assamese, Italian, Estonian,
Hungarian, Portuguese, Danish, Latvian)
* Make gdk_pixbuf_animation_new_from_file load png files (694148)
* Fix string formatting for l10n extraction (693534)
* Translation updates (Hebrew, Spanish, Brazilian Portuguese,
Slovenian, Galician, French, Catalan, Catalan (Valencian),
Malayalam, Slovak, Polish, Czech, Serbian, Uyghur, Norwegian
bokmål, Punjabi, Traditional Chinese)
* Allow loading animations from streams
* Allow loading animations from resources
* Fix cross-compiling for Windows and Wine (692072)
* Translation updates (Hungarian, German, Polish)
* The broken locking mechanism for loaders has been removed.
gdk-pixbuf now ignores loaders that are not marked as thread-safe.
b95cb49988