Properties in dom/locales/$lang/chrome/ allow detecting user locale

z3t reported a bunch of issues on HackerOne regarding detection of user locale with the help of dom/locales/$lang/chrome/ properties. PoCs done by z3t:

dom/dom.properties: https://people.torproject.org/~gk/tests/tor_form_locale_leak.html layout/xmlparser.properties: https://people.torproject.org/~gk/tests/tor_domparser_locale_leak.html layout/MediaDocument.properties: https://people.torproject.org/~gk/tests/tor_image_locale_leak.html