The ornamental design for a cabinet for a commercialaircraft passenger cabin lavatory, as shown and described.
FIG. 1 is a perspective view, taken from a front, right side, showing a cabinet for a commercial aircraft passenger cabin lavatory according to a first embodiment of our design;
FIG. 2 is a right side elevation view thererof, a left side elevation view being a mirror image thereof;
FIG. 3 is a perspective view, taken from a front, left side, showing a cabinet for a commercial aircraft passenger cabin lavatory according to a second embodiment of our design; and,
FIG. 4 is a left side elevation view thererof, a right side elevation view being a mirror image thereof.