Schema Browser Tree is not refreshed when adding parameters to a package (4237424)

When adding a parameter to a package script and re-compiling it, the nodes in the schema browser don't update to reflect this change, even if it's refreshed.
The only way to force it to refresh, is if you close and reopen the schema browser.

To replicate:
1. Create a new Package/Package Body:

====================================
CREATE OR REPLACE PACKAGE testz AS

FUNCTION MyFunction(Param1 IN NUMBER) RETURN NUMBER;
PROCEDURE MyProcedure(Param1 IN NUMBER,Param2 IN NUMBER,Param3 IN NUMBER);

END testz;
/

CREATE OR REPLACE PACKAGE BODY testz AS

FUNCTION MyFunction(Param1 IN NUMBER) RETURN NUMBER IS
BEGIN
RETURN Param1;
END;

PROCEDURE MyProcedure(Param1 IN NUMBER,Param2 IN NUMBER,Param3 IN NUMBER) IS
TmpVar NUMBER;
BEGIN
TmpVar := Param1;
END;

END testz;
/
====================================

2. View In Schema Browser Tree
3. Add a New Parameter to Procedure 'MyProcedure' & compile
4. View in Schema Browser Tree
5. Observe that the new parameter is displayed in the source on the right hand side, but not in the browser tree, even after a refresh.