Auto adding missing translations feature overwrites srcLang to current locale

[bocharsky-bw]

After enabling this feature the missing translation is added to the translations/messages.%current_locale%.xlf file only (which probably is on purpose) but also the srcLang attribute is changed to the current locale. It changes srcLang of every translation domain of the current locale, i.e. messages.uk.xlf, validators.uk.xlf, etc.). Here's the Git diff when I open the page with the missing translation in UK locale:

-<xliff xmlns="urn:oasis:names:tc:xliff:document:2.0" version="2.0" srcLang="en" trgLang="uk">
+<xliff xmlns="urn:oasis:names:tc:xliff:document:2.0" version="2.0" srcLang="uk" trgLang="uk">