[omemo] Keep compatibility with Gtk 3.20

omemo/gtk/config.py

@@ -220,10 +220,10 @@ class OMEMOConfigDialog(GajimPluginConfigDialog):
             pixbuf = GdkPixbuf.Pixbuf.new_from_file(path)
             self.qrcode.set_from_pixbuf(pixbuf)
             self.qrcode.show()
-            self.qrinfo.set_revealed(False)
+            self.qrinfo.hide()
         else:
-            self.qrinfo.set_revealed(True)
             self.qrcode.hide()
+            self.qrinfo.show()
 
     def human_hash(self, fpr):
         fpr = fpr.upper()

omemo/gtk/config.ui

@@ -33,8 +33,8 @@
         <child>
           <object class="GtkInfoBar" id="qrinfo">
             <property name="can_focus">False</property>
+            <property name="no_show_all">True</property>
             <property name="margin_bottom">6</property>
-            <property name="revealed">False</property>
             <child internal-child="action_area">
               <object class="GtkButtonBox">
                 <property name="can_focus">False</property>