I claim the ornamental design for a spill tray, as shown and described.
FIG. 1 is a top elevational view of a spill tray showing our new design.
FIG. 2 is a side elevational view thereof, all side elevational views being substantially identical thereto; and,
FIG. 3 is a cross-sectional view thereof taken along the line 3—3 shown in FIG. 1.
The bottom surface of the spill tray forms no part of the claimed design. The broken line disclosure of the U-shaped center cutout is for illustrative purposes only and forms no part of the claimed design.