The ornamental design for a massagechair, as shown and described.
FIG. 1 is a front perspective view of an embodiment of the massage chair;
FIG. 2 is a front view thereof;
FIG. 3 is a side view thereof;
FIG. 4 is an opposite view thereof;
FIG. 5 is a rear view thereof;
FIG. 6 is an alternative rear view thereof with a rear head rest portion removed;
FIG. 7 is a top view thereof;
FIG. 8 is a rear perspective view thereof;
FIG. 9 is an enlarged, fragmentary view thereof showing a side arm of the massage chair; and,
FIG. 10 is an enlarged, fragmentary view thereof showing an opposite side arm of the massage chair.
The broken lines shown in the figures are for the purpose of illustrating unclaimed portions of the invention and boundaries only and form no part of the claimed design.