Bug 1328643: Add some locking to prevent races caused by Cancel/Init from threads other than the target. r=froydnj

MozReview-Commit-ID: FdAPTGDNKup

xpcom/threads/TimerThread.cpp

@@ -287,10 +287,6 @@ nsTimerEvent::Run()
     return NS_OK;
   }
 
-  if (mGeneration != mTimer->GetGeneration()) {
-    return NS_OK;
-  }
-
   if (MOZ_LOG_TEST(GetTimerLog(), LogLevel::Debug)) {
     TimeStamp now = TimeStamp::Now();
     MOZ_LOG(GetTimerLog(), LogLevel::Debug,
@@ -298,7 +294,7 @@ nsTimerEvent::Run()
             this, (now - mInitTime).ToMilliseconds()));
   }
 
-  mTimer->Fire();
+  mTimer->Fire(mGeneration);
 
   // We call Cancel() to correctly release mTimer.
   // Read more in the Cancel() implementation.
@@ -378,7 +374,7 @@ TimerThread::Shutdown()
     }
 
     // Need to copy content of mTimers array to a local array
-    // because call to timers' ReleaseCallback() (and release its self)
+    // because call to timers' Cancel() (and release its self)
     // must not be done under the lock. Destructor of a callback
     // might potentially call some code reentering the same lock
     // that leads to unexpected behavior or deadlock.
@@ -390,7 +386,7 @@ TimerThread::Shutdown()
   uint32_t timersCount = timers.Length();
   for (uint32_t i = 0; i < timersCount; i++) {
     nsTimerImpl* timer = timers[i];
-    timer->ReleaseCallback();
+    timer->Cancel();
     ReleaseTimerInternal(timer);
   }
 
@@ -603,7 +599,7 @@ TimerThread::AddTimer(nsTimerImpl* aTimer)
 }
 
 nsresult
-TimerThread::RemoveTimer(nsTimerImpl* aTimer, bool aDisable)
+TimerThread::RemoveTimer(nsTimerImpl* aTimer)
 {
   MonitorAutoLock lock(mMonitor);
 
@@ -614,10 +610,6 @@ TimerThread::RemoveTimer(nsTimerImpl* aTimer, bool aDisable)
     return NS_ERROR_NOT_AVAILABLE;
   }
 
-  if (aDisable) {
-    aTimer->mEventTarget = nullptr;
-  }
-
   // Awaken the timer thread.
   if (mWaiting) {
     mNotified = true;