From 55fed9329600ee1c1369f5cfa71307d86c195b9a Mon Sep 17 00:00:00 2001
From: Nika Layzell <nika@thelayzells.com>
Date: Sat, 23 Mar 2019 12:56:19 +0100
Subject: [PATCH] Unregister ProcessHangMonitor as a hang annotator on
 shutdown.

---
 dom/ipc/ProcessHangMonitor.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/dom/ipc/ProcessHangMonitor.cpp b/dom/ipc/ProcessHangMonitor.cpp
index d46a1f5d5e..406d0bf0aa 100644
--- a/dom/ipc/ProcessHangMonitor.cpp
+++ b/dom/ipc/ProcessHangMonitor.cpp
@@ -323,6 +323,8 @@ HangMonitorChild::Shutdown()
 {
   MOZ_RELEASE_ASSERT(NS_IsMainThread());
 
+  BackgroundHangMonitor::UnregisterAnnotator(*this);
+
   MonitorAutoLock lock(mMonitor);
   while (!mShutdownDone) {
     mMonitor.Wait();