Don't make requests if we didn't manage to connect
Use QtConcurrent::run instead of QThread. QThread will issue the thread
immediately and that will overload the operating system giving "too many files
opened errors". QtConcurrent will do the appropriate balancing for us.
Test Plan: Doesn't crash on me anymore
Reviewed By: jgrulich
Differential Revision: https://phabricator.kde.org/D7785