Add a way to cancel deferred navigations in NavigationHandle

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..efb3ac9fb88c64c6376e4277ff085dd42da6793a 100644
--- a/content/browser/loader/navigation_resource_throttle.cc
+++ b/content/browser/loader/navigation_resource_throttle.cc
@@ -162,6 +162,8 @@ void NavigationResourceThrottle::OnUIChecksPerformed(
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   if (result == NavigationThrottle::CANCEL_AND_IGNORE) {
     controller()->CancelAndIgnore();
+  } else if (result == NavigationThrottle::CANCEL) {
+    controller()->Cancel();
   } else {
     controller()->Resume();
   }