FIG. 1 is a top plan view of an ornamental design for a chain breaker tool of the present invention in closed position;
FIG. 2 is a front view of an ornamental design for a chain breaker tool of the present invention in closed position;
FIG. 3 is a right side view of an ornamental design for a chain breaker tool of the present invention in closed position;
FIG. 4 is a rear view of an ornamental design for a chain breaker tool of the present invention in closed position;
FIG. 5 is a left side view of an ornamental design for a chain breaker tool of the present invention in closed position;
FIG. 6 is a bottom plan view of an ornamental design for a chain breaker tool of the present invention in closed position;
FIG. 7 is an upper left isometric view of an ornamental design for a chain breaker tool of the present invention in closed position;
FIG. 8 is an upper right isometric view of an ornamental design for a chain breaker tool of the present invention in closed position;
FIG. 9 is a top plan view of an ornamental design for a chain breaker tool of the present invention in open position;
FIG. 10 is a front view of an ornamental design for a chain breaker tool of the present invention in open position;
FIG. 11 is a right side view of an ornamental design for a chain breaker tool of the present invention in open position;
FIG. 12 is a rear view of an ornamental design for a chain breaker tool of the present invention in open position;
FIG. 13 is a left side view of an ornamental design for a chain breaker tool of the present invention in open position;
FIG. 14 is a bottom plan view of an ornamental design for a chain breaker tool of the present invention in open position;
FIG. 15 is an upper left isometric view of an ornamental design for a chain breaker tool of the present invention in open position; and,
FIG. 16 is an upper right isometric view of an ornamental design for a chain breaker tool of the present invention in open position.