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
/**
	 * Gets the element name. The object is a long string that separated with
	 * the separator "."
	 * 
	 * @param obj
	 *            the object
	 * @return the name behind the last separator "."
	 */
	public static String getElementName( Object obj )
	{
		if ( obj instanceof Class )
		{
			obj = ( (Class) obj ).getName( );
		}
		return obj.toString( )
				.substring( obj.toString( ).lastIndexOf( "." ) + 1 ); 
	}
	/**
	 * Gets the definition for the element with the specified name
	 * 
	 * @param elementName
	 *            the name of the element
	 * 
	 * @return Returns the definition, or null if the element is not defined.
	 */
	public static IElementDefn getElementDefn( String elementName )
	{
		IElementDefn defn = DesignEngine.getMetaDataDictionary( )
				.getElement( elementName );
		if ( defn == null )