ServiceWorker: Add running service worker check before claim a provider host.

content/browser/service_worker/service_worker_registration.cc

 // Copyright 2013 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_registration.h"
 
 #include "content/browser/service_worker/service_worker_context_core.h"
 #include "content/browser/service_worker/service_worker_info.h"
 #include "content/browser/service_worker/service_worker_register_job.h"
 #include "content/browser/service_worker/service_worker_utils.h"
@@ skipping 378 matching lines @@
     ServiceWorkerProviderHost* host = it->GetProviderHost();
     if (ShouldClaim(host, registrations))
       host->ClaimedByRegistration(this);
   }
   callback.Run(SERVICE_WORKER_OK);
 }
 
 bool ServiceWorkerRegistration::ShouldClaim(
     ServiceWorkerProviderHost* provider_host,
     const std::vector<ServiceWorkerRegistrationInfo>& registrations) {
+  if (provider_host->IsHostToRunningServiceWorker())
+    return false;
   if (provider_host->controlling_version() == active_version())
     return false;
 
   LongestScopeMatcher matcher(provider_host->document_url());
   if (!matcher.MatchLongest(pattern_))
     return false;
   for (const ServiceWorkerRegistrationInfo& info : registrations) {
     ServiceWorkerRegistration* registration =
         context_->GetLiveRegistration(info.registration_id);
     if (registration &&
         (registration->is_uninstalling() || registration->is_uninstalled()))
       continue;
     if (matcher.MatchLongest(info.pattern))
       return false;
   }
   return true;
 }
 
 }  // namespace content