Handles the -xml-strings service. 
This service was primarily helpful to developers and localizers to compare localized strings to the built in en strings. It's probably better to use our POT/PO workflow with your favorite tools, or simply diff the language header files directly. 
- Note
- The attribute idis not a specification, promise, or part of an API. You must not depend on this value. For strings meant for error output, thelabelattribute will contain the stringified version of the internal key for the string.