Add GetExpirationTimes() to HttpResponseHeader.

webkit/browser/appcache/appcache_update_job.cc

Index: webkit/browser/appcache/appcache_update_job.cc
diff --git a/webkit/browser/appcache/appcache_update_job.cc b/webkit/browser/appcache/appcache_update_job.cc
index 03bb909cf09e64bca4e879a469299410c2597c53..08fb45204d8d1cfcf58a53f69e2c99013984e04b 100644
--- a/webkit/browser/appcache/appcache_update_job.cc
+++ b/webkit/browser/appcache/appcache_update_job.cc
@@ -1237,10 +1237,12 @@ void AppCacheUpdateJob::OnResponseInfoLoaded(
     const std::string name = "vary";
     std::string value;
     void* iter = NULL;
-    if (!http_info->headers.get() ||
-        http_info->headers->RequiresValidation(http_info->request_time,
-                                               http_info->response_time,
-                                               base::Time::Now()) ||
+    base::Time expiration_time = base::Time();
+    if (http_info->headers) {
+      expiration_time = http_info->headers->GetExpirationTime(
+          http_info->request_time, http_info->response_time);
+    }
+    if (expiration_time <= base::Time::Now() ||
         http_info->headers->EnumerateHeader(&iter, name, &value)) {
       LoadFromNewestCacheFailed(url, response_info);
     } else {