Bug 191168 [Regression]Exception occurs when resize masterpage in library
Description: Exception occurs when resize masterpage in library. Build number:2.2.0.v20070606-0630 Regression bug:187443 Steps to reproduce: 1. New a library. 2. Go to Master Page, resize the master page using the ruler. Expected result: 1. Layout works correctly. 2. No exception is thrown out. Error log: An unexpected internal exception occurred.Please see log for detail. Plug-in Provider:Eclipse.org Plug-in Name:BIRT Designer UI Plug-in ID:org.eclipse.birt.report.designer.ui Version:2.2.0.v20070606-0630 Error Code:Error.GUIException.invokedByUnexpectedException Error Message:org.eclipse.birt.report.designer.internal.lib.lalyout.LibraryReportDesignLayout
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/Module.java
* Finds a theme in this module and its included modules.
	 * 
	 * @param name
	 *            Name of the style to find.
	 * @return The style, or null if the style is not found.
	 */
	public Theme findTheme( String name )
	{
		return (Theme) resolveElement( name, null, MetaDataDictionary
				.getInstance( ).getElement( ReportDesignConstants.THEME_ITEM ) );
	}
	/**
	 * Returns the theme of the report design/library.
	 * 
	 * @return the theme of the report design/library
	 */
	public Theme getTheme( )
	{
		if ( theme == null )
			return null;
		return (Theme) theme.getElement( );
	}
	/**
	 * Gets the name of the referenced theme on this element.
	 * 
	 * @return theme name. null if the theme is not defined on the element.
	 */
	public String getThemeName( )
	{
		if ( theme == null )