bug#46178: 28.0.50; auto-resize-tool-bars / auto-resize-tab-bars grow-only

[martin rudalics <rudalics@gmx.at>]

 >> That of 'recenter' does.  But since these options do not work out of the
 >> box (a user has to customize the option 'recenter-redisplay' too), it
 >> would be useful if the docs of 'auto-resize-tool-bars' and
 >> 'auto-resize-tab-bars' told so.  At the moment they just tell me to use
 >> M-x recenter or C-l.
 >
 > OK, I fixed that.

Thanks.  You won't believe it but yesterday this would have saved me
half an hour poking around with this.  Until then I didn't know that
'recenter' is now our moral equivalent of 'redisplay'.

You might also reconsider the Elisp manual entry where it says

      If this variable is non-‘nil’, the tool bar automatically resizes
      to show all defined tool bar items—but not larger than a quarter of
      the frame’s height.

I've been digging through Gerd's and Kim's rewrites of
'redisplay_tool_bar' and nowhere found a reference to that "quarter".
Did that ever work and when?

 >> We could stop mentioning 'grow-only' in the doc-strings and manuals and
 >> leave it in as an undocumented feature.
 >
 > You know me: I'm uneasy about downgrading features just because they
 > are awkward or inconvenient to document.

I stumbled across this feature because wrapping and unwrapping the tool
bar on Motif by changing the frame width shrinks the frame height for
inexplicable reasons until it is down to a few lines.  Lucid and
non-toolkit builds do not have this issue.  Currently, I just try to
understand the design considerations and whether they are responsible
for the behavior I see.

martin