Bug 176436 Charts Imported from Libraries do not update when libraries change
During a live presentation of BIRT at EclipseCon, we came across a rather embarassing issue. When charts are included in a library, and imported into a report design from a library, any changes to the library instance of the chart do not reflect in the report itself.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/DesignElementHandle.java
public void clearContents( int slotId ) throws SemanticException
	{
		SlotHandle slotHandle = getSlot( slotId );
		if ( slotHandle == null )
			return;
		for ( int i = slotHandle.getCount( ) - 1; i >= 0; i-- )
		{
			slotHandle.dropAndClear( i );
		}
	}
	/**
	 * Removes an existing user property definition from the element. This
	 * method will remove all existing values for the property, in both this
	 * element and all its derived elements.
	 * 
	 * @param propName
	 *            the name of the user property to remove
	 * @throws UserPropertyException
	 *             If the property is not found.
	 */
	public void dropUserPropertyDefn( String propName )
			throws UserPropertyException
	{
		DesignElement element = getElement( );
		UserPropertyCommand cmd = new UserPropertyCommand( module, element );
		cmd.dropUserProperty( propName );
	}
	/**
	 * Returns a handle to the element that this element extends.
	 *