Prevent the destruction of WebContents in NavigationThrottle methods

content/browser/loader/navigation_resource_throttle.cc

Index: content/browser/loader/navigation_resource_throttle.cc
diff --git a/content/browser/loader/navigation_resource_throttle.cc b/content/browser/loader/navigation_resource_throttle.cc
index 3c76bae826fb64108c5e8b54bee16fc02f5d0234..7c9be230b8553ea175cff9bc274322f2a4ddf949 100644
--- a/content/browser/loader/navigation_resource_throttle.cc
+++ b/content/browser/loader/navigation_resource_throttle.cc
@@ -26,7 +26,8 @@ typedef base::Callback<void(NavigationThrottle::ThrottleCheckResult)>
 void SendCheckResultToIOThread(UIChecksPerformedCallback callback,
                                NavigationThrottle::ThrottleCheckResult result) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  CHECK(result != NavigationThrottle::DEFER);
+  CHECK(result != NavigationThrottle::DEFER &&
+        result != NavigationThrottle::DESTROYED);
   BrowserThread::PostTask(BrowserThread::IO, FROM_HERE,
                           base::Bind(callback, result));
 }