If log_path is empty, we shouldn't setChatLogsDir to it.
In fact, this may have been the cause of something Nomade Zhao brought up.
Also, InstantMessageLogPathAnyAccount was accidentally being set as a PerAccount
Also removed some code from the Mac/windows code in
indra/plugins/filepicker/llfilepicker.cpp that shouldn't
be in there anymore (send_agent_pause/resume and updating
the LLFrameTimer stuff).