Empty RSIs that have states pasted to them do not inherit the size of the other RSI/DMI

[DrSmugleaf]

• Import a non 32x32 .dmi
• Copy a state
• Create a new RSI
• Paste the state
• New RSI remains 32x32 (the default) and crops the sprite instead

If empty, the size of the RSI should be changed as well when states are pasted into it.