WIP: Permit extension tags in xmlish attribute values

Authored by Arlolra on Tue, Jan 9, 10:10 PM.

Description

WIP: Permit extension tags in xmlish attribute values

Added support for <translate> in the attribute

Bug: T183515
Authored-by: Arlo Breault <abreault@wikimedia.org>
Authored-by: Shannon Bailey <sbailey@wikimedia.org>
Change-Id: I311d0fbbd2cdcf2a0c0a3dbf698912e6df5f3356