[Bug 30512] Main menu appears truncated though there is lots of room for the whole menu

[seguso]

Public bug reported:
https://launchpad.net/malone/bugs/30512

Affects: gnome-applets (Ubuntu)
       Severity: Normal
       Priority: (none set)
         Status: Unconfirmed

Description:
Swap the position of the two panels, so that the menu bar (Application-
Places-System) on the bottom panel.

Click to open the menu (e.g. click "Places").

If the menu icons were not loaded in memory, Gnome places the menu too
close to the bottom of the screen, so only a fraction of it is visible,
and I have to scroll to see all the items. This looks very wrong since
there is plently of space in the screen: the menu ought to have appeared
at a higher position.

I believe the reason for the problem is the following. If the icons are not loaded, Gnome computes the menu height ignoring the icons, i.e. considering only the text height. And it chooses a menu position that is correct with THAT height. Then, when the icons are loaded, the menu height increases, but Gnome does not update the menu position, so the menu ends up too low and gets truncated.
I am using dapper, but this happens on breezy too.