Bug 193467 URL hyperlink can't work in chart viewer
chart/org.eclipse.birt.chart.reportitem/src/org/eclipse/birt/chart/reportitem/ChartReportItemPresentationImpl.java
sExtension = getFirstSupportedFormat( sSupportedFormats );
			}
		}
		else
		{
			if ( isOutputRendererSupported( outputFormat ) )
			{
				sExtension = outputFormat;
			}
			else
			{
				sExtension = getFirstSupportedFormat( sSupportedFormats );
			}
		}
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.engine.extension.IReportItemPresentation#setSupportedImageFormats(java.lang.String)
	 */
	public void setSupportedImageFormats( String sSupportedFormats )
	{
		this.sSupportedFormats = sSupportedFormats;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.engine.extension.IReportItemPresentation#deserialize(java.io.InputStream)
	 */
	public void deserialize( InputStream is )