Bug 1707924 - Assert on DelayedRunnable dispatch on non debug builds. r=xpcom-reviewers,nika

This assertion currently only happens on debug builds, but attempts to dispatch delayed runnables after we have started or finished cancelling all delayed runnables in a TaskQueue may be causing shutdown hangs.

Differential Revision: https://phabricator.services.mozilla.com/D113839

xpcom/threads/TaskQueue.cpp

@@ -108,10 +108,8 @@ void TaskQueue::AwaitShutdownAndIdle() {
 }
 
 void TaskQueue::OnDelayedRunnableCreated(DelayedRunnable* aRunnable) {
-#ifdef DEBUG
   MonitorAutoLock mon(mQueueMonitor);
-  MOZ_ASSERT(!mDelayedRunnablesCancelPromise);
-#endif
+  MOZ_RELEASE_ASSERT(!mDelayedRunnablesCancelPromise);
 }
 
 void TaskQueue::OnDelayedRunnableScheduled(DelayedRunnable* aRunnable) {