The ornamental design for a frontbumper for an automobile, as shown and described.
FIG. 1 is a front perspective view of a front bumper for an automobile of our new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is a bottom plan view thereof;
FIG. 6 is a right-side view thereof; and,
FIG. 7 is a left-side view thereof.
A second embodiment of the design is the same as in FIGS. 1–7 without the rear view shown in FIG. 3. Thus, the second embodiment is depicted in FIGS. 1, 2, and 4–7.