Bug 1401366. P2 - bail out Observe() if not subcribed per comment 2. …

…r=kaku MozReview-Commit-ID: 4LEBD3g0OwX --HG-- extra : rebase_source : c31cb94eeb52b06a3f327492b918e93c82b83616
dothq · Sep 20, 2017 · 16f3e9d · 16f3e9d
1 parent ed0a449
commit 16f3e9d
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/dom/html/HTMLMediaElement.cpp b/dom/html/HTMLMediaElement.cpp
@@ -3773,7 +3773,11 @@ class HTMLMediaElement::ShutdownObserver : public nsIObserver
 
   NS_IMETHOD Observe(nsISupports*, const char* aTopic, const char16_t*) override
   {
-    MOZ_DIAGNOSTIC_ASSERT(mPhase == Phase::Subscribed);
+    if (mPhase != Phase::Subscribed) {
+      // Bail out if we are not subscribed for this might be called even after
+      // |nsContentUtils::UnregisterShutdownObserver(this)|.
+      return NS_OK;
+    }
     MOZ_DIAGNOSTIC_ASSERT(mWeak);
     if (strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID) == 0) {
       mWeak->NotifyShutdownEvent();