Static field initialization order bug in LoggingEventSource causes ParseFilterSpec to silently produce wrong rules #127681

 LoggingEventSource.<cctor>()                                              // Something ends up calling LoggingEventSource.Instance (probably on a log statement) which triggers static .
   LoggingEventSource.Instance = new LoggingEventSource() 
     EventSource(EventSourceSettings.EtwSelfDescribingEventFormat)          // base ctor
       Initialize(guid, name, traits)
         eventPipeProvider.Register(guid, name)
           EventPipeInternal.CreateProvider(name, &Callback, ctx)
             [native: EventPipe already has this provider enabled in active session]
             [native: calls Callback synchronously]
             // This callback sets  the HandleEnableNotification as a deferred command.
         [back in Initialize()]
         EventListener.AddEventSource(this)
         lock (EventListenersLock) {
           deferredCommands = m_deferredCommands
           DoCommand(deferredCommands)
               OnEventCommand(args)
                LoggingEventSource.OnEventCommand(args)                       // OVERRIDE
                  SetFilterSpec(value)                                        
                    ParseFilterSpec(filterSpec, defaultLevel)
                      filterSpec.Split(s_semicolon, ...)                      // s_semicolon is null.  splits on whitespace instead of ';'
         }
         m_completelyInited = true
     [constructor finishes]
   s_semicolon = new char[] { ';' }                                        // TOO LATE
   s_colon = new char[] { ':' }
 // .cctor finishes