UI: pass the untransformed node size to the shader

[mockersf]

Objective

• Add border radius to UI nodes (adopted) #12500 broke rotating ui nodes, see examples pbr (missing "metallic" label) or overflow_debug (bottom right box is empty)

Solution

• Pass the untransformed node size to the shader

[JMS55]

Do we have an example/test for this? If not, do you mind adding one? This is the second time we've seen a UI rotation bug like this :(

[mockersf]

It's used in two examples: pbr and overflow_debug. I would prefer to not add a dedicated example as modifying the transform of ui nodes is not something I would like to encourage until we have a good solution for in-layout and out-of-layout rotations