We claim the ornamental design for a tub filler, as shown and described.
FIG. 1 is a top, front, right perspective view of a tub filler;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a rear elevation view thereof;
FIG. 4 is a right side elevation view thereof;
FIG. 5 is a left side elevation view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The broken lines shown in the drawings illustrate portions of the tub filler that form no part of the claim. The tub filler is shown with a symbolic break in its length. The appearance of any portion of the article between the break lines forms no part of the claim.