Adds a point to this rectangle. The resulting rectangle is the
smallest rectangle that contains both the original rectangle and the
After adding a point, a call to contains(point) with the added
point as an argument does not necessarily return true.
The rectangle.contains(point) method does not return true
for points on the right or bottom edges of a rectangle. Therefore, if the
added point falls on the left or bottom edge of the enlarged rectangle,
rectangle.contains(point) returns false for that point.