Bug 147407 Preview the attached report in the web viewer first time and then click the TOC button will cause NPE error
Description: It just can be reprouduced at first time preview. Step to reproduce: 1. please use attach report file 2. preview it in the web viewer 3. click the "Toggle table of contents" button Actual result: As the atteched screenshot shows,There is a NPE error.And if you preview it in the Web viewer again, the phenomenon is disappear.But reopen the eclipse and preview it at first time, it will be occured.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/utility/ParameterAccessor.java
* 
	 * @param string
	 *            the string to process.
	 * @return a string which is not null and without excessive spaces.
	 */
	protected static String preProcess( String string )
	{
		return string == null ? "" : string.trim( ); 
	}
	/**
	 * Convert UTF-8 string into ISO-8895-1
	 * 
	 * @param s
	 *            UTF-8 string
	 * @return
	 */
	protected static String toISOString( String s )
	{
		String ISOString = s;
		if ( s != null )
		{
			try
			{
				ISOString = new String( s.getBytes( UTF_8_ENCODE ),
						ISO_8859_1_ENCODE );
			}
			catch ( UnsupportedEncodingException e )
			{
				ISOString = s;
			}