Check the existence of provider_host in ServiceWorkerURLTrackingRequestHandler::MaybeCreateJob()

content/browser/service_worker/service_worker_provider_host.cc

Index: content/browser/service_worker/service_worker_provider_host.cc
diff --git a/content/browser/service_worker/service_worker_provider_host.cc b/content/browser/service_worker/service_worker_provider_host.cc
index 0e83e84ce0cf87791c8e326e9e45a13914a4236c..92fc4cf7a5331ccb60b2dcb0fb80d1951be1ab1a 100644
--- a/content/browser/service_worker/service_worker_provider_host.cc
+++ b/content/browser/service_worker/service_worker_provider_host.cc
@@ -60,6 +60,9 @@ class ServiceWorkerURLTrackingRequestHandler
       net::URLRequest* request,
       net::NetworkDelegate* network_delegate,
       ResourceContext* resource_context) override {
+    // |provider_host_| may have been deleted when the request is resumed.
+    if (!provider_host_)
+      return nullptr;
     const GURL stripped_url = net::SimplifyUrlForRequest(request->url());
     provider_host_->SetDocumentUrl(stripped_url);
     provider_host_->SetTopmostFrameUrl(request->first_party_for_cookies());