The ornamental design for a mascarabrush, as shown and described.
FIG. 1 is a perspective view of a mascara brush showing my new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom plan view thereof;
FIG. 8 is an enlarged front view of the encircled region of FIG. 2; and,
FIG. 9 is an enlarged perspective view of the encircled region of FIG. 1.
The dot-dash broken line circles in FIGS. 1, 2, 8, and 9 delineates a portion of the mascara brush that is part of the claimed design and that is shown on an enlarged scale in FIGS. 8 and 9. The dashed broken lines throughout the drawing figures depict portions of the mascara brush that form no part of the claimed design.