resize_mini_window question

[Ergus]

Hi Eli:

As you know I have been working in icomplete-vertical and I just
received an issue that has to do with resize_mini_window function more
than with icomplete.

They are related with this bugs:

https://debbugs.gnu.org/cgi/bugreport.cgi?bug=24293
https://debbugs.gnu.org/cgi/bugreport.cgi?bug=39379

The problem to me seems that the function xdisp.c:resize_mini_window
uses FRAME_LINE_HEIGHT(f); to resize; but in the report the user sets a
different font for the minibuffer. So when it sets
Vmax_mini_window_height to an int

Vmax_mini_window_height * unit is a "wrong" value and the lines will not
fit.

I see 3 possible clean solutions:

1) Modify resize_mini_window to use the minibuffer's font size to
calculate the height when Vmax_mini_window_height is an int. (don't know
if it is possible to access the minibuffer font size from there or if
this could produce some undesired side effect)

2) Modify the documentation of max-mini-window-height to specify that if
an integer, it specifies a number of lines respecting to the frame's
default font, not the minibuffer's visible lines.

3) Just force the text to fit ignoring that the number of real visible
lines will be different than max-mini-window-height. (This will be seen
as ignoring the max-mini-window-height)

What do you think is better?
Best,
Ergus