The ornamental design for a decorativecharm, as shown and described.
FIG. 1 is a perspective view of a decorative charm shown in a position of use with an unclaimed container drawn in broken lines inserted into the decorative charm;
FIG. 2 is a perspective view thereof shown with the unclaimed container removed;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a front elevational view thereof;
FIG. 5 is a left side elevational view thereof;
FIG. 6 is a right side elevational view thereof;
FIG. 7 is a top plan view thereof; and,
FIG. 8 is a bottom plan view thereof.
The broken lines illustrating a container in FIG. 1 depict environmental structure and form no part of the claimed design. All other broken lines depict portions of the decorative charm that form no part of the claimed design.