novnc

Remove double unescaping of title

Commit fa5b334dcbe7a5dab21580b54cc2f5f142600379 by Joel Martin changed
getQueryVal() to always decode the value using decodeURIComponent(), but
unescape() is still used for extracting the title, leading to
double-unescaping.

As unescape() is deprecated anyway, remove the last user.

Cc: Joel Martin <github@martintribe.org>
Cc: Anthony Young <sleepsonthefloor@gmail.com>