bug#14825: 24.3.50; split-window-below miscounts window lines

[martin rudalics]

>> How would you report the size of an internal window composed of two leaf
>> windows showing buffers with different default character sizes?
>
> As a sum of the line counts of the two children, obviously.

That would mean lots of fun.  Consider an Emacs frame built from three
windows like this

 ------------------
|        |         |
|   A    |         |
|        |         |
|--------|    B    |
|        |         |
|   C    |         |
|        |         |
 ------------------

where A and B have the same character heights and the one of C is twice
that.  The parent window of A and C would have a larger height than B.
How would window_resize_check handle that?

martin

PS: It can be easily done as soon as we do resizing pixelwise.  But it
would break a few functions like `window-edges' in the sense that the
lower edge of A would not be necessary equal to the upper edge of C.