Return a list of the edge coordinates of WINDOW.
WINDOW must be a valid window and defaults to the selected one.
The returned list has the form (LEFT TOP RIGHT BOTTOM). TOP and BOTTOM
count by lines, and LEFT and RIGHT count by columns, all relative to 0,
0 at top left corner of frame.
RIGHT is one more than the rightmost column occupied by WINDOW. BOTTOM
is one more than the bottommost row occupied by WINDOW. The edges
include the space used by WINDOW's scroll bar, display margins, fringes,
header line, and/or mode line. For the edges of just the text area, use
`window-inside-edges'.
(fn &optional WINDOW)