bug#858: Conflict between ERC mode tracking and ibuffer window shrinking

[Chong Yidong]

Hi guys,

Could you take a look at this bug report?  I'm not sure whether ERC or
ibuffer needs fixing.

> There is a bug when using conjointly these two features. Here are the
> relevant portions of configuration :
>
> ;;make ibuffer resize itself to its buffer size
> (setq ibuffer-use-other-window t)
> (setq ibuffer-default-shrink-to-minimum-size t)
>
> No specific configuration for erc, just enabling tracker is enough.
> Then, run erc, and, in any erc buffer, call ibuffer. The screen
> briefly flashes as an ERC window opens then disappears, and the
> ibuffer window is reduced to a much smaller size than what it would be
> outside ERC. I think the issue is erc's hook to
> window-configuration-change somehow messing with ibuffer, but I'm not
> experienced enough to find where the bug is.