Which signal is emitted when the arrow in GtkComboBoxEntry() is pressed?

[Egon Andersen <post talura dk>]

Hi,

During my migration from GtkCombo() I experienced that I miss a signal 
when the 'arrow' at the right of the GtkComboBoxEntry() is pressed.
I can't seem to find the relevant signal.
When GtkCombo() was used I used "set-focus-child", but that doesn't do 
the trick any more.
I've searched and experimented with a number of possible (and 
impossible) signals without luck.

Best regards
Egon Andersen

(This is used to trigger the re-build I was mentioning in an earlier 
post today on this list.)