The ornamental design for a shower headcontroller, as shown and described.
FIG. 1 is a perspective view of a shower head controller showing my new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom plan view thereof; and,
FIG. 8 is a perspective schematic view illustrating an application of a shower head controller showing my design.
The broken lines shown in FIGS. 1 through 8 are for the purpose of illustrating portions of the shower head controller and form no part of the claimed design. The broken lines showing a shower head in FIG. 8 are for the purpose of illustrating environment and form no part of the claimed design.