Bug 1157323 - Part 6: Some comment improvements. r=froydnj

MozReview-Commit-ID: GDLuJS0Wlgh

--HG--
extra : rebase_source : 6156b6ab99aa7b429bec55b0e32500074d59f7a6
extra : source : 32ed23f6341788882a076134a62ae5717c2fbf02

xpcom/threads/nsTimerImpl.h

@@ -145,16 +145,16 @@ public:
   // for use when logging timer firings.
   Name mName;
 
-  // These members are set by Init and never reset.
-  CallbackType          mCallbackType;
-
   // These members are set by the initiating thread, when the timer's type is
   // changed and during the period where it fires on that thread.
+  CallbackType          mCallbackType;
   uint8_t               mType;
 
   // The generation number of this timer, re-generated each time the timer is
   // initialized so one-shot timers can be canceled and re-initialized by the
   // arming thread without any bad race conditions.
+  // This is only modified on the target thread, and only after removing the
+  // timer from the TimerThread. Is set on the arming thread, initially.
   int32_t               mGeneration;
 
   uint32_t              mDelay;