Bug 145520 Group name will not show up in group list if the group use default name and key expression has no value
Description: Group name will not show up in group list if key expression has no value. Steps to reproduce: 1. Insert a table into report, bind it to a data set 2. Switch to property editor -> groups 3. Click on add button to open new group dialog, then press ok button Expected result: A new group with default name will be added to group list Actual result: A new group is added to group list, but without group name. But when let group tab lost focus and get focus again, you can see the group name.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/command/ContentCommand.java
content, false );
		ActivityStack stack = getActivityStack( );
		stack.startFilterEventTrans( dropRecord.getLabel( ) );
		try
		{
			doDelectAction( content, unresolveReference );
		}
		catch ( SemanticException ex )
		{
			stack.rollback( );
			throw ex;
		}
		
		stack.execute( dropRecord );
		stack.commit( );
	}
	/**
	 * Changes derived elements to derive from the parent (if any) instead.
	 * 
	 * @param obj
	 *            the element to clean up
	 * @throws ExtendsException
	 *             if an error occurs, but the operation should not fail under
	 *             normal conditions
	 */
	private void adjustDerived( DesignElement obj ) throws ExtendsException
	{
		
		Collection derived = obj.getDerived( );
		if ( derived.isEmpty( ) )