ID 278501 - GafferThree: UIDelegate subclasses cannot make use of menu actions defined in their superclasses

Problem summary:

Customers and partners have the ability to extend GafferThree with custom package types. Such package might subclass from built-in package types, like light filters.

Package types which define custom menu actions via the delegate's getMenuActions() can be subclassed, but those subclasses cannot make use of the superclass's actions - they simply don't show up in the menu, and no error message is logged.

Steps to reproduce:

1. Download PrmanLightFilterGafferPackage.tgz and unpack it to /tmp/plugins/UIPlugins
2. Launch Katana with /tmp/plugins in your KATANA_RESOURCES
3. Create, edit and view a GafferThree node
4. Create a light
5. Create a vanilla light filter via the 'F' key
6. Create a prman light filter via the 'P' key
7. Compare the two light filters' context menus.

Expected behaviour:

The Promote to Top Level action is available from both menus.

Actual behaviour:

The Promote to Top Level action is only available from the vanilla light filter menu.

Reproduced versions/platforms:

• 2.5v6

Customer version/platform:

Not supplied