Report native allocation size of AnimatedImageDrawable

Bug: 73641604
Test: infeasible

Fix nNativeByteSize's return value to be jlong, instead of long.
Add up the bytes used by the SkAnimatedImage and SkPictures and store
them on the AnimatedImageDrawable for registration.
Note that this is an approximation, and it assumes it will be drawn to a
hardware canvas and animated.