domain: Drop stable_defaults wrapper

Have callers invoke it directly on Guest

virtManager/addhardware.py

@@ -483,7 +483,7 @@ class vmmAddHardware(vmmGObjectUI):
                 disk_bus_types.append("sata")
                 disk_bus_types.append("fdc")
 
-                if not vm.stable_defaults():
+                if not vm.xmlobj.stable_defaults():
                     disk_bus_types.append("scsi")
                     disk_bus_types.append("usb")
 
@@ -633,7 +633,7 @@ class vmmAddHardware(vmmGObjectUI):
         # Type name, desc
         for t in char_class.TYPES:
             if (t in stable_blacklist and
-                self.vm.stable_defaults()):
+                self.vm.xmlobj.stable_defaults()):
                 continue
 
             desc = char_class.pretty_type(t)

virtManager/choosecd.py

@@ -81,7 +81,7 @@ class vmmChooseCD(vmmGObjectUI):
     def reset_state(self):
         self.mediacombo.reset_state()
 
-        enable_phys = not self.vm.stable_defaults()
+        enable_phys = not self.vm.xmlobj.stable_defaults()
         self.widget("physical-media").set_sensitive(enable_phys)
         self.widget("physical-media").set_tooltip_text("" if enable_phys else
             _("Physical CDROM passthrough not supported with this hypervisor"))

virtManager/domain.py

@@ -365,9 +365,6 @@ class vmmDomain(vmmLibvirtObject):
     def get_install_abort(self):
         return bool(self._install_abort)
 
-    def stable_defaults(self):
-        return self.get_xmlobj().stable_defaults()
-
     def has_spicevmc_type_redirdev(self):
         devs = self.xmlobj.devices.redirdev
         for dev in devs: