We claim the ornamental design for a shower controller, as shown and described.
FIG. 1 is a perspective view of an embodiment of a shower controller of the claimed design;
FIG. 2 is a front view of the claimed design shown in FIG. 1;
FIG. 3 is a top view of the claimed design shown in FIG. 1;
FIG. 4 is a bottom view of the claimed design shown in FIG. 1;
FIG. 5 is a side view of the claimed design shown in FIG. 1; and,
FIG. 6 is another side view of the claimed design shown in FIG. 1.
The ornamental design that is claimed is shown in the drawings as solid lines and surfaces having surface shading. The broken lines in the drawings are for illustrative purposes only and form no part of the claimed design. For example, broken lines formed by equal length dashes show unclaimed portions of the design. Broken lines formed of unequal length dashes (i.e., dash-dot) show boundaries between either claimed and unclaimed portions of the design or between unclaimed and unclaimed portions of the design.