[Pidgin] #5205: Crash on GTK < 2.6 when topic==NULL in pidgin_conv_update_fields()

[Pidgin]

#5205: Crash on GTK < 2.6 when topic==NULL in pidgin_conv_update_fields()
--------------------------+-------------------------------------------------
 Reporter:  dseven        |       Type:  defect
   Status:  new           |   Priority:  minor 
Component:  pidgin (gtk)  |    Version:  2.4.0 
 Keywords:                |    Pending:  0     
--------------------------+-------------------------------------------------
 pidgin/gtkconv.c ~line 6497, there's a section entitled:

                         /* GTK < 2.6 doesn't have auto ellipsization, so
 we do a crude
                          * trucation to prevent forcing the window to be
 as wide as the topic */

 Unfortunately the following code is not careful enough to check if
 topic==NULL before it tries to use it, and all sorts of bad things start
 happening when it is, as is the case when attempting to join an AIM chat
 that doesn't exist.

 Suggested fix attached.

-- 
Ticket URL: <http://developer.pidgin.im/ticket/5205>
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