Bug 155509 ModuleHandle findResource method does not support .properties files
There is no fileType for .properties files in IResourceLocator
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/Module.java
}
	/**
	 * 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 )
			return null;
		return theme.getName( );
	}
	/**
	 * Returns the resolved theme of the report design/library.
	 * 
	 * @param module
	 *            the module to resolve the theme
	 * @return the resolved theme of the report design/library
	 */