Bug 214706 Script UID doens't work for Chart
Use chart "onRender" property handle and call ModuleUtil.getScriptUID(), it generates the id. But later use this id to get back the PropertyHandle or Script content, it fails.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/PropertyHandle.java
* Adds a report item to the property with the given element handle. The
	 * report item must not be newly created and not yet added to the design.
	 * 
	 * @param content
	 *            handle to the newly created element
	 * @throws SemanticException
	 *             if the element is not allowed to insert
	 */
	public void add( DesignElementHandle content ) throws SemanticException
	{
		if ( content == null )
			return;
		ContentCommand cmd = new ContentCommand( getModule( ),
				new ContainerContext( getElement( ), propDefn.getName( ) ) );
		cmd.add( content.getElement( ) );
	}
	/**
	 * Adds a report item to this property at the given position. The item must
	 * not be newly created and not yet added to the design.
	 * 
	 * @param content
	 *            handle to the newly created element
	 * @param newPos
	 *            the position index at which the content to be inserted,
	 *            0-based integer
	 * @throws SemanticException
	 *             if the element is not allowed to insert
	 */
	public void add( DesignElementHandle content, int newPos )
			throws SemanticException