Bug 173236 NPE is thrown when opening a design file that is created by a higher version BIRT
1. New a report, switch to xml-source view. 2. Edit the version number in line 2, from 3.2.10 to 3.2.11 and save. 3. Close the report and reopen it. The xml-source view is opened automatically. Switch to lay-out view, there's an error message window, and NPE is thrown in error-log view. When user is trying to open a design file that is created by a higher version BIRT, model will throw an exception and stop parsing the report design file. UI should 1. Prevent the NPE 2. Telling user that he is using a higher version design file that this build does not support. (Catch the exception and reflect the message in the exception to end user)
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/ErrorDetail.java
*            <li><code>DesignFileException.SEMANTIC_WARNING</code>
	 *            <li><code>DesignFileException.SYNTAX_ERROR</code>
	 *            </ul>
	 * @return a list containing specified semantic errors. Each element in the
	 *         list is <code>ErrorDetail</code>.
	 */
	public static List getSemanticErrors( List errors, String errorType )
	{
		ArrayList retList = new ArrayList( );
		for ( int i = 0; i < errors.size( ); i++ )
		{
			ErrorDetail errorDetail = (ErrorDetail) errors.get( i );
			if ( errorType.equalsIgnoreCase( errorDetail.getType( ) ) )
			{
				retList.add( errorDetail );
			}
		}
		return retList;
	}
	/**
	 * Returns the reference to the editor.
	 * 
	 * @return The reference to the editor.For example graphic editor, xml
	 *         source editor, script editor and so on.
	 */
	public String getSubEditor( )
	{
		return subEditor;
	}
}