Bug 167542 A parameter group isn't deleted after moving it to another parameter group through DND
Drag a parameter group and drop it to another one is a "move" operation, which cuts the source and pastes to the destination. But the source one isn't deleted in such operation while the parameters in the group are all deleted.
UI/org.eclipse.birt.report.designer.core/src/org/eclipse/birt/report/designer/util/DNDUtil.java
}
		return obj;
	}
	/**
	 * Gets the length of elements in object
	 * 
	 * @param obj
	 * @return the length of elements in object
	 */
	public static int getObjectLength( Object obj )
	{
		if ( obj == null )
		{
			return 0;
		}
		else if ( obj instanceof StructuredSelection )
		{
			return getObjectLength( ( (StructuredSelection) obj ).toArray( ) );
		}
		else if ( obj instanceof Object[] )
		{
			return ( (Object[]) obj ).length;
		}
		return 1;
	}
	/**
	 * Checks whether child's container exists in handle array
	 * 
	 * @param content
	 *            child handle