Bug 189622 DesignElementHandle.getMethods( ) shouldn't return null value
The return type of DesignElementHandle.getMethods( ) is List; if the design element handle doesn't have script methods, then it return null value. The return value is empty list will be better.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/extension/PeerExtensibilityProvider.java
String extensionName )
	{
		super( element, extensionName );
	}
	/**
	 * Returns the read-only list of all property definitions, including not
	 * only those defined in Model and extension definition file, but those
	 * defined by <code>IReportItem</code>. The returned list is read-only,
	 * so no modification is allowed on this list. Each one in list is the
	 * instance of <code>IPropertyDefn</code>.
	 * 
	 * @return the read-only list of all property definitions. Return empty list
	 *         if there is no property defined.
	 */
	public List getPropertyDefns( )
	{
		List props = super.getPropertyDefns( );
		PeerExtensionElementDefn extDefn = (PeerExtensionElementDefn) getExtDefn( );
		
		
		if ( extDefn == null )
			return props;
		
		IPropertyDefinition[] dynamicProps = getExtensionModelPropertyDefns( );
		if ( dynamicProps != null )
		{
			for ( int i = 0; i < dynamicProps.length; i++ )
			{
				IPropertyDefinition extProp = dynamicProps[i];
				props.add( new ExtensionModelPropertyDefn( extProp, extDefn