service worker: Implement NavigationPreloadManager.setHeaderValue

content/browser/service_worker/service_worker_registration.h

Index: content/browser/service_worker/service_worker_registration.h
diff --git a/content/browser/service_worker/service_worker_registration.h b/content/browser/service_worker/service_worker_registration.h
index d332fca5fc6195ae3c97b5985ab2115097e78ab8..0efc111087c6b79ec0fad09318e6d71adbc084de 100644
--- a/content/browser/service_worker/service_worker_registration.h
+++ b/content/browser/service_worker/service_worker_registration.h
@@ -96,7 +96,11 @@ class CONTENT_EXPORT ServiceWorkerRegistration
   }
 
   bool is_navigation_preload_enabled() const {
-    return is_navigation_preload_enabled_;
+    return navigation_preload_state_.enabled;
+  }
+
+  const std::string& navigation_preload_header() const {
+    return navigation_preload_state_.header;
   }
 
   ServiceWorkerVersion* GetNewestVersion() const;
@@ -155,6 +159,7 @@ class CONTENT_EXPORT ServiceWorkerRegistration
       scoped_refptr<base::SingleThreadTaskRunner> task_runner);
 
   void EnableNavigationPreload(bool enable);
+  void SetNavigationPreloadHeader(const std::string& value);
 
  private:
   friend class base::RefCounted<ServiceWorkerRegistration>;
@@ -198,7 +203,7 @@ class CONTENT_EXPORT ServiceWorkerRegistration
   bool is_uninstalling_;
   bool is_uninstalled_;
   bool should_activate_when_ready_;
-  bool is_navigation_preload_enabled_;
+  NavigationPreloadState navigation_preload_state_;
   base::Time last_update_check_;
   int64_t resources_total_size_bytes_;