Bug 312761 It makes no difference changing the series labels position in Radar chart.[13]
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/model/type/impl/PieSeriesImpl.java
/**
	 * This is true if the Ratio attribute has been set.
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @generated
	 * @ordered
	 */
	protected boolean ratioESet;
	/**
	 * The default value of the '{@link #getRotation() <em>Rotation</em>}' attribute.
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @see #getRotation()
	 * @generated
	 * @ordered
	 */
	protected static final double ROTATION_EDEFAULT = 0.0;
	/**
	 * The cached value of the '{@link #getRotation() <em>Rotation</em>}' attribute.
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @see #getRotation()
	 * @generated
	 * @ordered
	 */
	protected double rotation = ROTATION_EDEFAULT;
	/**
	 * This is true if the Rotation attribute has been set.
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->