Bug 148515 [Regression] User properties can't be found in properties view(chart)
[Regression] User properties can't be found in properties view(chart) Steps: 1.Create a chart 2.Open property editor view, select User Porperties, add "abc" string 3.Open properties view Actual Results: 1.user properties are not displayed. Expected Resulst:L 1.user properties should be displayed.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/extension/ExtensibilityProvider.java
{
	/**
	 * The design element which is extendable.
	 */
	protected DesignElement element;
	/**
	 * The overridden extension element definition.
	 */
	protected ExtensionElementDefn cachedExtDefn = null;
	/**