[ServiceWorkr] Add NULL check of provider_host_ in ServiceWorkerControlleeRequestHandler's callbacks

content/browser/service_worker/service_worker_controllee_request_handler.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/service_worker/service_worker_controllee_request_handler.h"
 
 #include "base/debug/trace_event.h"
 #include "content/browser/service_worker/service_worker_context_core.h"
 #include "content/browser/service_worker/service_worker_metrics.h"
 #include "content/browser/service_worker/service_worker_provider_host.h"
@@ skipping 118 matching lines @@
       stripped_url,
       base::Bind(&self::DidLookupRegistrationForMainResource,
                  weak_factory_.GetWeakPtr()));
 }
 
 void
 ServiceWorkerControlleeRequestHandler::DidLookupRegistrationForMainResource(
     ServiceWorkerStatusCode status,
     const scoped_refptr<ServiceWorkerRegistration>& registration) {
   DCHECK(job_.get());
-  provider_host_->SetAllowAssociation(true);
+  if (provider_host_)
+    provider_host_->SetAllowAssociation(true);
   if (status != SERVICE_WORKER_OK) {
     job_->FallbackToNetwork();
     TRACE_EVENT_ASYNC_END1(
         "ServiceWorker",
         "ServiceWorkerControlleeRequestHandler::PrepareForMainResource",
         job_.get(),
         "Status", status);
     return;
   }
   DCHECK(registration.get());
 
   // Initiate activation of a waiting version.
   // Usually a register job initiates activation but that
   // doesn't happen if the browser exits prior to activation
   // having occurred. This check handles that case.
   if (registration->waiting_version())
     registration->ActivateWaitingVersionWhenReady();
 
   scoped_refptr<ServiceWorkerVersion> active_version =
       registration->active_version();
 
   // Wait until it's activated before firing fetch events.
   if (active_version.get() &&
       active_version->status() == ServiceWorkerVersion::ACTIVATING) {
-    provider_host_->SetAllowAssociation(false);
+    if (provider_host_)
+      provider_host_->SetAllowAssociation(false);
     registration->active_version()->RegisterStatusChangeCallback(
         base::Bind(&self::OnVersionStatusChanged,
                    weak_factory_.GetWeakPtr(),
                    registration,
                    active_version));
     TRACE_EVENT_ASYNC_END2(
         "ServiceWorker",
         "ServiceWorkerControlleeRequestHandler::PrepareForMainResource",
         job_.get(),
         "Status", status,
         "Info", "Wait until finished SW activation");
     return;
   }
 
   if (!active_version.get() ||
       active_version->status() != ServiceWorkerVersion::ACTIVATED) {
     job_->FallbackToNetwork();
     TRACE_EVENT_ASYNC_END2(
         "ServiceWorker",
         "ServiceWorkerControlleeRequestHandler::PrepareForMainResource",
         job_.get(),
         "Status", status,
         "Info",
         "ServiceWorkerVersion is not available, so falling back to network");
     return;
   }
 
   ServiceWorkerMetrics::CountControlledPageLoad();
 
-  provider_host_->AssociateRegistration(registration.get());
+  if (provider_host_)
+    provider_host_->AssociateRegistration(registration.get());
   job_->ForwardToServiceWorker();
   TRACE_EVENT_ASYNC_END2(
       "ServiceWorker",
       "ServiceWorkerControlleeRequestHandler::PrepareForMainResource",
       job_.get(),
       "Status", status,
       "Info",
       "Forwarded to the ServiceWorker");
 }
 
 void ServiceWorkerControlleeRequestHandler::OnVersionStatusChanged(
     ServiceWorkerRegistration* registration,
     ServiceWorkerVersion* version) {
-  provider_host_->SetAllowAssociation(true);
+  if (provider_host_)
+    provider_host_->SetAllowAssociation(true);
   if (version != registration->active_version() ||
       version->status() != ServiceWorkerVersion::ACTIVATED) {
     job_->FallbackToNetwork();
     return;
   }
 
   ServiceWorkerMetrics::CountControlledPageLoad();
 
-  provider_host_->AssociateRegistration(registration);
+  if (provider_host_)
+    provider_host_->AssociateRegistration(registration);
   job_->ForwardToServiceWorker();
 }
 
 void ServiceWorkerControlleeRequestHandler::PrepareForSubResource() {
   DCHECK(job_.get());
   DCHECK(context_);
   DCHECK(provider_host_->active_version());
   job_->ForwardToServiceWorker();
 }
 
 }  // namespace content