Create ServiceWorkerProviderHost before starting worker

content/browser/service_worker/service_worker_version.h

Index: content/browser/service_worker/service_worker_version.h
diff --git a/content/browser/service_worker/service_worker_version.h b/content/browser/service_worker/service_worker_version.h
index ef267112f83f15932416276a09f650c3d7924f25..c747c0c34f763888d465e99c4a3f4cf3046c977a 100644
--- a/content/browser/service_worker/service_worker_version.h
+++ b/content/browser/service_worker/service_worker_version.h
@@ -304,6 +304,13 @@ class CONTENT_EXPORT ServiceWorkerVersion
     return controllee_map_;
   }
 
+  // The provider host hosting this version. Only valid while the version is
+  // running.
+  ServiceWorkerProviderHost* provider_host() {
+    DCHECK(provider_host_);
+    return provider_host_.get();
+  }
+
   base::WeakPtr<ServiceWorkerContextCore> context() const { return context_; }
 
   // Adds and removes |request_job| as a dependent job not to stop the
@@ -733,6 +740,11 @@ class CONTENT_EXPORT ServiceWorkerVersion
 
   std::set<const ServiceWorkerURLRequestJob*> streaming_url_request_jobs_;
 
+  // Keeps track of the provider hosting this running service worker for this
+  // version. |provider_host_| is always valid as long as this version has
+  // the running context.
+  base::WeakPtr<ServiceWorkerProviderHost> provider_host_;
+
   std::map<std::string, ServiceWorkerProviderHost*> controllee_map_;
   // Will be null while shutting down.
   base::WeakPtr<ServiceWorkerContextCore> context_;