Tests cyrillic xhr content is correctly loaded in inspector.
    https://bugs.webkit.org/show_bug.cgi?id=79026

http://127.0.0.1:8000/devtools/network/resources/cyrillic.html?sync
resource.content: The following line contains a word "success" written with cyrillic letters.
SUССЕSS

http://127.0.0.1:8000/devtools/network/resources/cyrillic.html?async
resource.content: The following line contains a word "success" written with cyrillic letters.
SUССЕSS