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
processData( dataContent );
			return dataContent;
		}
		return foreignContent;
	}
	/**
	 * localzie the text.
	 * 
	 * @param key
	 *            text key
	 * @param text
	 *            default text
	 * @return localized text.
	 */
	private String localize( IContent content, String key, String text )
	{
		assert ( content != null );
		if ( content.getGenerateBy( ) != null )
		{
			DesignElementHandle element = ( (ReportItemDesign) content
					.getGenerateBy( ) ).getHandle( );
			if ( key != null && element != null )
			{
				String t = ModuleUtil.getExternalizedValue( element, key, text,
						ULocale.forLocale( locale ) );
				if ( t != null )
				{
					return t;
				}
			}