Introduce FetchEventPreloadHandle to pass the preload response to FetchEvent.

content/renderer/service_worker/service_worker_context_client.cc

Index: content/renderer/service_worker/service_worker_context_client.cc
diff --git a/content/renderer/service_worker/service_worker_context_client.cc b/content/renderer/service_worker/service_worker_context_client.cc
index 6dfc4b1ee6d164db427db7c042c5c69db7cc65c2..c55db893e36921a8536659c8629b75a1b6608af9 100644
--- a/content/renderer/service_worker/service_worker_context_client.cc
+++ b/content/renderer/service_worker/service_worker_context_client.cc
@@ -237,6 +237,7 @@ class ServiceWorkerContextClient::FetchEventDispatcherImpl
 
   void DispatchFetchEvent(int fetch_event_id,
                           const ServiceWorkerFetchRequest& request,
+                          mojom::FetchEventPreloadHandlePtr preload_handle,
                           const DispatchFetchEventCallback& callback) override {
     ServiceWorkerContextClient* client =
         ServiceWorkerContextClient::ThreadSpecificInstance();
@@ -244,6 +245,11 @@ class ServiceWorkerContextClient::FetchEventDispatcherImpl
       callback.Run(SERVICE_WORKER_ERROR_ABORT, base::Time::Now());
       return;
     }
+    if (preload_handle) {
+      // TODO(horo): Implement this to pass |preload_handle| to FetchEvent.
+      NOTIMPLEMENTED();
+      return;
+    }
     client->DispatchFetchEvent(fetch_event_id, request, callback);
   }