Bug 207268 Add visibility option for plot within axes
For chart with axes, we should make plot within axes invisible. Meantime, other plots, such as axes, legend and title, should be visible. This enhancement doesn't include UI change, and it is required for cross tab integration.
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/model/layout/LayoutPackage.java
/**
	 * Returns the meta object for class '{@link org.eclipse.birt.chart.model.layout.TitleBlock <em>Title Block</em>}'.
	 * <!-- begin-user-doc --> <!-- end-user-doc -->
	 * @return the meta object for class '<em>Title Block</em>'.
	 * @see org.eclipse.birt.chart.model.layout.TitleBlock
	 * @generated
	 */
	EClass getTitleBlock( );
	/**
	 * Returns the factory that creates the instances of the model. <!--
	 * begin-user-doc --> <!-- end-user-doc -->
	 * 
	 * @return the factory that creates the instances of the model.
	 * @generated
	 */
	LayoutFactory getLayoutFactory( );
	/**
	 * <!-- begin-user-doc -->
	 * Defines literals for the meta objects that represent
	 * <ul>
	 *   <li>each class,</li>
	 *   <li>each feature of each class,</li>
	 *   <li>each enum,</li>
	 *   <li>and each data type</li>
	 * </ul>
	 * <!-- end-user-doc -->
	 * @generated
	 */
	interface Literals
	{