Bug 153040 Template definition should be removed after the report item is deleted
Steps to reproduce: 1.New a report, extends lib.label 2.Convert the label to template report item, and revert it back to the report item 3.Delete the label 4.Remove the included library Expected result: Library can be removed Actual result: A BIRT exception occurred. Plug-in Provider:Eclipse.org Plug-in Name:BIRT Model Plug-in ID:org.eclipse.birt.report.model Version:2.1.0.v20060808-0630 Error Code:Error.LibraryException.LIBRARY_HAS_DESCENDENTS Error Message:The library "Lib" can no be dropped because it has descendents "NewLabel" in the current module.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/core/UserPropertyDefn.java
* 
	 */
	public String getDisplayName( )
	{
		
		if ( !StringUtil.isBlank( displayName ) )
		{
			
			return displayName;
		}
		
		return name;
	}
	/**
	 * Sets the display name of the property. Use this only for testing; you
	 * should normally set the display name message ID so that the name can be
	 * retrieved from a message catalog and localized.
	 * 
	 * @param theName
	 *            the display name to set
	 */
	public void setDisplayName( String theName )
	{
		displayName = theName;
	}
	/**
	 * Sets the (anonymous) set of choices for a property. The choices are
	 * stored here directly, they are not named and stored in the data
	 * dictionary as are choices for system properties.
	 *