The ornamental design for an adapter for a videogame controller, as shown and described.
FIG. 1 is a front elevational view of an adapter for a video game controller showing my new design;
FIG. 2 is a top plan view of FIG. 1;
FIG. 3 is a bottom plan view of FIG. 1;
FIG. 4 is a rear elevation view of FIG, 1;
FIG. 5 is an enlarged top plan view of the adapter shown separately for clarity;
FIG. 6 is a left side elevational view of FIG. 5, the right side elevational view being a mirror image thereof;
FIG. 7 is a front elevational view of FIG. 5; and,
FIG. 8 is a rear elevational view of FIG. 5.
In FIGS. 1, 3, 4, 5, 7, and 8 all broken lines within the boundaries of the adapter shown in solid lines represent parts of the adapter that do not form part of the claimed design, and that are shown for illustrative purposes only. In FIGS. 1 to 4, all other broken lines represent the environment of the video game controller, which does not form part of the claimed design and that is shown for illustrative purposes only.