This is the first step into introducing support for Android 9 patch
format (extension: .9.png). The principle is to expose a new property
on image object that define a complete behavior incompatible with other
border and fill logic. The reason is that 9 patch allow for any number
of stretchable area inside an image, not just for each corner. The way
to define this is by giving a pointer to an array of the proper type
that define stretchable region relative to each other.
The logic being slightly more complex than the border and fill logic,
it is slightly slower. If you are just defining corner on your image
for something like a button, you would still get better performance
using border. I will try to make edje_cc detect those case and fallback
to border when possible.
Depends on D9095