The ornamental design for a holder for an electronicdevice, as shown and described.
FIG. 1 is a front perspective view of a holder for an electronic device showing our new design;
FIG. 2 is a top view thereof;
FIG. 3 is a bottom view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a rear view thereof; and,
FIG. 7 is a front view thereof.
The broken line showing of various regions in FIGS. 1–7, including the unshaded areas therein, is for illustrative purposes only and forms no part of the claimed design.