SignalR/SignalR — pull request #3065 by moozzyk (2014-06-02 17:38:11+00:00)
Title: BetterThreadSafeThanSorry - fixing UrlBuilder threading issue

The same instance of UrlBuilder could be used by multiple threads which could corrupt the internal state of the StringBuilder instance used by the UrlBuilder which results in weird exceptions. This manifested as random CI build failures. The fix is to create a new instance each time instead of having a re-usable class variable.