Bug 120218 Right click menu option to apply theme.
We should support the following right click menu. -- User right clicks int he report design layout area. -- The following menu items needs to be supported Theme --> Apply Theme -->Theme1 -->Theme2 ( similar to Apply style menu option )
UI/org.eclipse.birt.report.designer.core/src/org/eclipse/birt/report/designer/util/DEUtil.java
return spt;
	}
	/**
	 * If given value if null, return an empty string, or return itself.
	 * 
	 * @param value
	 *            a String value.
	 * @return non-null value.
	 */
	public static String resolveNull( String value )
	{
		return value == null ? "" : value; 
	}
	/**
	 * Converts the RGB object value to a String, the String format is "r,g,b",
	 * no quotation marks.
	 * 
	 * @param rgb
	 *            RGB value.
	 * @return String value.
	 */
	public static String getRGBText( RGB rgb )
	{
		if ( rgb != null )
		{
			return rgb.red + "," + rgb.green + "," + rgb.blue; 
		}
		return ""; 
	}
	/**