Bug 190981 The image id of image in different pages are the same
The id of image generated by the same report item (such as chart) are the same, thought the image contents are in different pages.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/presentation/LocalizedContentVisitor.java
* <li> format the value
	 * <li> handle it as it is an text.
	 * 
	 * @param data
	 *            data object
	 */
	protected void processData( IDataContent data )
	{
		String helpText = localize( data, data.getHelpKey( ), data.getHelpText( ) );
		data.setHelpText( helpText );
		String text = ""; 
		if ( data.getLabelKey( ) != null || data.getLabelText( ) != null )
		{
			text = localize( data, data.getLabelKey( ), data.getLabelText( ) );
		}
		else
		{
			Object value = data.getValue( );
			if ( value != null )
			{
				IStyle style = data.getComputedStyle( );
				if ( value instanceof Number )
				{
					String format = style.getNumberFormat( );
					NumberFormatter fmt = context.getNumberFormatter( format );
					text = fmt.format( (Number) value );
					CSSValue align = style
							.getProperty( IStyle.STYLE_NUMBER_ALIGN );
					if ( align != null && align != CSSValueConstants.NONE_VALUE )
					{