ServiceWorker: Update the install sequence as per the latest spec

content/common/service_worker/service_worker_messages.h

Index: content/common/service_worker/service_worker_messages.h
diff --git a/content/common/service_worker/service_worker_messages.h b/content/common/service_worker/service_worker_messages.h
index 1362f0952c58bab981f37ac96ede5b0e1463d898..7c27308f6020034ef5cd1533a8882da80a374f72 100644
--- a/content/common/service_worker/service_worker_messages.h
+++ b/content/common/service_worker/service_worker_messages.h
@@ -65,6 +65,7 @@ IPC_STRUCT_TRAITS_BEGIN(content::ServiceWorkerRegistrationObjectInfo)
 IPC_STRUCT_TRAITS_END()
 
 IPC_STRUCT_TRAITS_BEGIN(content::ServiceWorkerVersionAttributes)
+  IPC_STRUCT_TRAITS_MEMBER(changed_mask)
   IPC_STRUCT_TRAITS_MEMBER(installing)
   IPC_STRUCT_TRAITS_MEMBER(waiting)
   IPC_STRUCT_TRAITS_MEMBER(active)
@@ -185,10 +186,11 @@ IPC_MESSAGE_ROUTED1(ServiceWorkerHostMsg_CacheStorageKeys,
 // on the correct thread.
 
 // Response to ServiceWorkerMsg_RegisterServiceWorker.
-IPC_MESSAGE_CONTROL3(ServiceWorkerMsg_ServiceWorkerRegistered,
+IPC_MESSAGE_CONTROL4(ServiceWorkerMsg_ServiceWorkerRegistered,
                      int /* thread_id */,
                      int /* request_id */,
-                     content::ServiceWorkerRegistrationObjectInfo)
+                     content::ServiceWorkerRegistrationObjectInfo,
+                     content::ServiceWorkerVersionAttributes)
 
 // Response to ServiceWorkerMsg_UnregisterServiceWorker.
 IPC_MESSAGE_CONTROL2(ServiceWorkerMsg_ServiceWorkerUnregistered,
@@ -210,13 +212,18 @@ IPC_MESSAGE_CONTROL3(ServiceWorkerMsg_ServiceWorkerStateChanged,
                      blink::WebServiceWorkerState)
 
 // Tells the child process to set service workers for the given provider.
-IPC_MESSAGE_CONTROL5(ServiceWorkerMsg_SetVersionAttributes,
+IPC_MESSAGE_CONTROL4(ServiceWorkerMsg_SetVersionAttributes,
                      int /* thread_id */,
                      int /* provider_id */,
                      int /* registration_handle_id */,
-                     int /* changed_mask */,
                      content::ServiceWorkerVersionAttributes)
 
+// Informs the child process that new ServiceWorker enters the installation
+// process.
+IPC_MESSAGE_CONTROL2(ServiceWorkerMsg_UpdateFound,
+                     int /* thread_id */,
+                     content::ServiceWorkerRegistrationObjectInfo)
+
 // Tells the child process to set the controller ServiceWorker for the given
 // provider.
 IPC_MESSAGE_CONTROL3(ServiceWorkerMsg_SetControllerServiceWorker,