The ornamental design for a frontend of a vehicle, as shown and described.
FIG. 1 is a right front perspective view of a front end of a vehicle.
FIG. 2 is a left rear perspective view of the vehicle shown in FIG. 1.
FIG. 3 is a front view thereof.
FIG. 4 is a left side view thereof.
FIG. 5 is a right side view thereof; and,
FIG. 6 is a top view thereof.
The de-emphasized and half-tone portions illustrate environmental structures. These portions form no part of the claimed design. The front end of a vehicle is shown within broken lines, and any elements shown outside the broken lines form no part of the claimed design.