The ornamental design for an electroniccontroller for a gas discharge lamp, as shown and described.
FIG. 1 shows the front view of the electronic controller for a gas discharge lamp;
FIG. 2 shows the rear view of the electronic controller;
FIG. 3 shows the top view of the electronic controller;
FIG. 4 shows the bottom of the electronic controller;
FIG. 5 shows the right of the electronic controller, the broken lines in FIG. 5 are included for the purpose of illustrating a portion of the electronic controller that forms no part of the claimed design;
FIG. 6 shows the left view of the electronic controller; and,
FIG. 7 shows the perspective view of the electronic controller.