GtkComboBox popup should disappear on press, not release

Submitted by Johan Dahlin

Description

When clicking outside of the popped up window the button is not closing when the button is pressed, instead it's closed when it's released. This behavior is fine when clicking inside the window, but for clicks outside it should be on pressed.

This is how combobox entries behaves in both qt and win32.

Version: 3.22.x