ServiceWorker: Cleanup ServiceWorkerVersion

- Remove unused friendliness
- Remove DCHECK and if-statement combination forbidden by our coding standard
http://www.chromium.org/developers/coding-style#TOC-CHECK-DCHECK-and-NOTREACHED-
- Make some instance variables const

BUG=n/a
TEST=n/a

Review URL: https://codereview.chromium.org/1100003005

Cr-Commit-Position: refs/heads/master@{#326740}

content/browser/service_worker/service_worker_version.cc

@@ -370,8 +370,9 @@ ServiceWorkerVersion::ServiceWorkerVersion(
     int64 version_id,
     base::WeakPtr<ServiceWorkerContextCore> context)
     : version_id_(version_id),
-      registration_id_(kInvalidServiceWorkerVersionId),
+      registration_id_(registration->id()),
       script_url_(script_url),
+      scope_(registration->pattern()),
       status_(NEW),
       context_(context),
       script_cache_map_(this, context),
@@ -379,10 +380,6 @@ ServiceWorkerVersion::ServiceWorkerVersion(
       weak_factory_(this) {
   DCHECK(context_);
   DCHECK(registration);
-  if (registration) {
-    registration_id_ = registration->id();
-    scope_ = registration->pattern();
-  }
   context_->AddLiveVersion(this);
   embedded_worker_ = context_->embedded_worker_registry()->CreateWorker();
   embedded_worker_->AddListener(this);

content/browser/service_worker/service_worker_version.h

@@ -312,11 +312,11 @@ class CONTENT_EXPORT ServiceWorkerVersion
  private:
   friend class base::RefCounted<ServiceWorkerVersion>;
   friend class ServiceWorkerURLRequestJobTest;
+  friend class ServiceWorkerVersionBrowserTest;
+
   FRIEND_TEST_ALL_PREFIXES(ServiceWorkerControlleeRequestHandlerTest,
                            ActivateWaitingVersion);
   FRIEND_TEST_ALL_PREFIXES(ServiceWorkerVersionTest, IdleTimeout);
-  FRIEND_TEST_ALL_PREFIXES(ServiceWorkerVersionTest, KeepAlive);
-  FRIEND_TEST_ALL_PREFIXES(ServiceWorkerVersionTest, ListenerAvailability);
   FRIEND_TEST_ALL_PREFIXES(ServiceWorkerVersionTest, SetDevToolsAttached);
   FRIEND_TEST_ALL_PREFIXES(ServiceWorkerWaitForeverInFetchTest, RequestTimeout);
   FRIEND_TEST_ALL_PREFIXES(ServiceWorkerFailToStartTest, Timeout);
@@ -324,7 +324,6 @@ class CONTENT_EXPORT ServiceWorkerVersion
                            TimeoutStartingWorker);
   FRIEND_TEST_ALL_PREFIXES(ServiceWorkerVersionBrowserTest,
                            TimeoutWorkerInEvent);
-  friend class ServiceWorkerVersionBrowserTest;
 
   typedef ServiceWorkerVersion self;
   using ServiceWorkerClients = std::vector<ServiceWorkerClientInfo>;
@@ -489,9 +488,10 @@ class CONTENT_EXPORT ServiceWorkerVersion
       ServiceWorkerStatusCode default_code);
 
   const int64 version_id_;
-  int64 registration_id_;
-  GURL script_url_;
-  GURL scope_;
+  const int64 registration_id_;
+  const GURL script_url_;
+  const GURL scope_;
+
   Status status_;
   scoped_ptr<EmbeddedWorkerInstance> embedded_worker_;
   std::vector<StatusCallback> start_callbacks_;