Bug 140395 IImage.getID() return null on chart images
When I use image.getID() to retrieve ID of chart image, it always returns null.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/impl/Image.java
return data;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.engine.api2.IImage#getImageStream()
	 */
	public InputStream getImageStream( )
	{
		switch ( this.source )
		{
			case IImage.FILE_IMAGE :
				try
				{
					URL url = new URL( this.id );
					return new BufferedInputStream( url.openStream( ) );
				}
				catch ( MalformedURLException e )
				{
				}
				catch ( IOException e1 )
				{
				}
				try
				{
					return new BufferedInputStream( new FileInputStream( new File( this.id ) ) );
				}
				catch ( FileNotFoundException e )
				{
					logger.log( Level.SEVERE, e.getMessage( ), e );