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
Object value = source.extensionPropValues.get( propName );
			if ( value == null )
				continue;
			Object valueToSet = ModelUtil.copyValue( propDefn, value );
			if ( valueToSet == null )
				continue;
			extensionPropValues.put( propName, valueToSet );
			
			
			if ( propDefn.getTypeCode( ) == IPropertyType.ELEMENT_TYPE )
			{
				if ( propDefn.isList( ) )
				{
					List values = (ArrayList) valueToSet;
					for ( int i = 0; i < values.size( ); i++ )
					{
						DesignElement item = (DesignElement) values.get( i );
						item.setContainer( element, propName );
					}
				}
				else
				{
					( (DesignElement) valueToSet ).setContainer( element,
							propName );
				}
			}
		}
	}
	/**
	 * Return the extension element, which implements the interface