Bug 143173 No error for recursive including when exporting a report to a library
Steps to reproduce: 1.New a library named "Lib", add a lable in it 2.New a report, extends Lib.label 3.Export the report, choose target library "Lib" Expected result: Error to warn the recursive including Actual result: The target library includes itself without error
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/util/ModelUtil.java
{
		IElementDefn defn = MetaDataDictionary.getInstance( ).getElement(
				elementName );
		return containElement( element, defn );
	}
	/**
	 * Sets default time zone. Wrote this method becuase of bugs in ICUs.
	 */
	public static void setDefaultTimeZone( )
	{
		java.util.TimeZone defaultTimeZone = java.util.TimeZone.getDefault( );
		SimpleTimeZone pdt = new SimpleTimeZone(
				defaultTimeZone.getRawOffset( ), defaultTimeZone.getID( ) );
		SimpleTimeZone.setDefault( pdt );
	}
	/**
	 * Gets the copy of the given element.
	 * 
	 * @param element
	 *            the element to copy
	 * @return the copy of the element
	 */
	public static DesignElement getCopy( DesignElement element )
	{
		if ( element == null )
			return null;
		try
		{
			DesignElement copy = (DesignElement) element.clone( );
			assert copy != null;