The ornamental design for a hubunitbearing, as shown and described.
FIG. 1 is a front view of a hub unit bearing showing my new design;
FIG. 2 is a rear view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a bottom view thereof;
FIG. 5 is a right side view thereof, a left side view being a mirror image thereof; and,
FIG. 6 is an exploded view thereof.
In the drawings, the dashed broken lines depict portions of the hub unit bearing that form no part of the claim. The dot-dash broken lines represent the boundary of the claimed design and form no part of the claim.