Bug 1036679 - MediaStreamGraph shutdown can hang if happening in conjunction with a memory report. r=roc

content/media/MediaStreamGraph.cpp

@@ -2789,9 +2789,15 @@ MediaStreamGraphImpl::CollectReports(nsIHandleReportCallback* aHandleReport,
       EnsureImmediateWakeUpLocked(monitorLock);
     }
 
-    // Wait for the report to complete.
+    if (mLifecycleState >= LIFECYCLE_WAITING_FOR_THREAD_SHUTDOWN) {
+      // Shutting down, nothing to report.
+      return NS_OK;
+    }
+
+    // Wait for up to one second for the report to complete.
     nsresult rv;
-    while ((rv = memoryReportLock.Wait()) != NS_OK) {
+    const PRIntervalTime kMaxWait = PR_SecondsToInterval(1);
+    while ((rv = memoryReportLock.Wait(kMaxWait)) != NS_OK) {
       if (PR_GetError() != PR_PENDING_INTERRUPT_ERROR) {
         return rv;
       }