Porting GTK+ app from defining custom stock items to using GtkIconTheme

[Bálint Réczey <balint balintreczey hu>]

Hi,

I'm trying to move Wireshark from using the deprecated
gtk_toggle_tool_button_new_from_stock(), etc. API to use
gtk_toggle_tool_button_new() and friends instead.

Wireshark defines many custom icons icons, but they can't be properly
set on buttons/toolbars or in menus. The ones loaded XPM format appear
scaled up while
the ones loaded from inline pixbufs do not appear at all.
Stock GTK+ icons work fine.

What do I miss? I could not find relevant parts in the new API, the
original code worked fine.

I have tested the code with GTK 3.6 and 3.10 on Debian Wheezy and
experimental respectively.

Thanks in advance,
Balint