bug#2423: 23.0.90; Incomplete text in tooltip for buffer's encoding

[martin rudalics]

> In "emacs -Q", move the mouse pointer to the mnemonic of
> buffer-file-coding-system, and wait for the tooltip to pop up.  The
> tooltip text should be:
>
>   Buffer coding systme (multi-byte): CODING
>   mouse-1: describe coding system
>
> But on MS-Windows, if CODING is iso-latin-N-dos (for any N that is a
> single digit), the second line is not shown; instead, there's an empty
> line.

On Windows XP I never get a decent last line for ANY multiline tooltip
when the default variable-pitch font is used (sometimes a few dots are
displayed instead of the last line).  With Courier New all tooltips are
shown as created.

martin