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/elements/ExtendedItem.java
ElementPropertyDefn propDefn = super.getPropertyDefn( propName );
		if ( propDefn != null )
			return propDefn;
		if ( provider != null )
			return (ElementPropertyDefn) provider.getPropertyDefn( propName );
		return propDefn;
	}
	/**
	 * Gets the list of property definitions available to this element. Includes
	 * all properties defined for this element, all user-defined properties
	 * defined on this element or its ancestors, any style properties that this
	 * element supports and extension properties that the extended element of
	 * this item supports.
	 * 
	 * @see org.eclipse.birt.report.model.core.DesignElement#getPropertyDefns()
	 */
	public List getPropertyDefns( )
	{
		if ( provider != null )
			return provider.getPropertyDefns( );
		return super.getPropertyDefns( );
	}
	/**
	 * Gets the definition of the extension element.
	 * 
	 * @return the definition of the extension element if found, or null if the
	 *         extended item is not extensible or the extension element is not
	 *         registered in BIRT
	 */
	public ExtensionElementDefn getExtDefn( )