Bug 179431 [Automation]Chart background color issue[0602]
Details: [Automation]Chart background color issue[0602] Step: 1. Add a chart and set output format as jpg/bmp. 2. Add a chart and set output format as png/svg. Actual result: Step 1: Background color of chart is baby blue. Step 2: Background color of chart is black.
chart/org.eclipse.birt.chart.device.extension/src/org/eclipse/birt/chart/device/image/JavaxImageIOWriter.java
IIOWriteWarningListener,
		IImageMapEmitter
{
	protected Image _img = null;
	protected Object _oOutputIdentifier = null;
	private Bounds _bo = null;
	private transient boolean _bImageExternallySpecified = false;
	private static ILogger logger = Logger.getLogger( "org.eclipse.birt.chart.device.extension/image" ); 
	private final static String NO_OP_JAVASCRIPT = "javascript:void(0);"; 
	private final static String POLY_SHAPE = "poly"; 
	private boolean bAddCallback = false;
	/**
	 * Returns the output format string for this writer.
	 * 
	 * @return
	 */
	protected abstract String getFormat( );
	/**
	 * Returns the output image type for this writer.
	 * 
	 * @see java.awt.image.BufferedImage#TYPE_INT_RGB
	 * @see java.awt.image.BufferedImage#TYPE_INT_ARGB
	 * @see java.awt.image.BufferedImage#TYPE_INT_ARGB_PRE