Validate wallpaper dimension while generating crop

If dimensions of cropped wallpaper exceed max texture size that GPU can
support, it will cause sysui keep crashing because it can not initialize
egl with an appropriate surface.

Bug: 120847476.
Test: Write a custom app to set a 8000x800 bitmap as wallpaper.
Test: The cropped file will be 29600x2960 and make sysui keep crashing.
Test: After applyed this cl, wallpaper will use fallback.
Test: Sysui will not keep crashing any more.
Change-Id: Icdc6292191d1e966c52640f4c1a5a154dfba45d3