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.extension/src/org/eclipse/birt/chart/device/swing/SwingTextRenderer.java
{
			clrBackground = (Color) _sxs.getColor( (ColorDefinition) la.getBackground( ) );
		}
		double dAngleInRadians = ( ( -dAngleInDegrees * Math.PI ) / 180.0 );
		final ITextMetrics itm = new SwingTextMetrics( _sxs, la );
		final double dFW = itm.getFullWidth( );
		final double dH = itm.getHeight( );
		final double dD = itm.getDescent( );
		final double dFH = itm.getFullHeight( );
		double dXOffset = 0, dW = 0;
		final int iLC = itm.getLineCount( );
		final Insets ins = la.getInsets( )
				.scaledInstance( _sxs.getDpiResolution( ) / 72d );
		final double shadowness = 3 * _sxs.getDpiResolution( ) / 72d;
		
		final boolean bEmptyText = "".equals( la.getCaption( ).getValue( ) ); 
		TextLayout tl;
		final HorizontalAlignment ha = la.getCaption( )
				.getFont( )
				.getAlignment( )
				.getHorizontalAlignment( );
		final boolean bRightAligned = ha.getValue( ) == HorizontalAlignment.RIGHT;
		final boolean bCenterAligned = ha.getValue( ) == HorizontalAlignment.CENTER;
		double dCosTheta = Math.abs( Math.cos( dAngleInRadians ) );
		double dSineTheta = Math.abs( Math.sin( dAngleInRadians ) );
		dX -= dFW / 2;
		
		if ( dAngleInDegrees == 0 )
		{
			if ( bShadow )