Bug 194549 Memory leak in chart device renderers
After memory analysis for Chart code, it indicates java.awt.Font objects are not garbage collected. Investigating the renderer code, Graphics2D objects in IDisplayServer and IDeviceRenderer are not disposed after chart rendering finished. Need to invoke IDeviceRenderer.dispose() after ChartReportItemPresentationImpl being finished, and dispose all required resources in that method, including IDisplayServer and anything else.
chart/org.eclipse.birt.chart.device.svg/src/org/eclipse/birt/chart/device/svg/SVGRendererImpl.java
*/
	protected Document dom;
	/**
	 * SVG Graphic context
	 */
	protected SVGGraphics2D svggc;
	/**
	 * Property that determines if the SVG should resize to the containing
	 * element dimensions.
	 */
	protected boolean _resizeSVG = false;
	
	/**
	 * Property that determines if the generated SVG output should contain embedded javascript code.
	 */
	public boolean _enableScript = true;
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.chart.device.IDeviceRenderer#setProperty(java.lang.String,
	 *      java.lang.Object)
	 */
	public void setProperty( String sProperty, Object oValue )
	{
		super.setProperty( sProperty, oValue );
		if ( sProperty.equals( IDeviceRenderer.UPDATE_NOTIFIER ) )
		{
			_iun = (IUpdateNotifier) oValue;
			ivRenderer.setIUpdateNotifier( _iun );
		}