Add GetExpirationTimes() to HttpResponseHeader.

content/browser/appcache/appcache_update_job.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/appcache/appcache_update_job.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/compiler_specific.h"
 #include "base/strings/string_util.h"
@@ skipping 1454 matching lines @@
   const GURL& url = found->second;
 
   if (!http_info) {
     LoadFromNewestCacheFailed(url, NULL);  // no response found
   } else {
     // Check if response can be re-used according to HTTP caching semantics.
     // Responses with a "vary" header get treated as expired.
     const std::string name = "vary";
     std::string value;
     size_t iter = 0;
+    net::HttpResponseHeaders::ExpirationTimes expiration_times =
+        http_info->headers->GetExpirationTimes(http_info->request_time,
+                                               http_info->response_time);
     if (!http_info->headers.get() ||
-        http_info->headers->RequiresValidation(http_info->request_time,

[gavinp, 2016/04/29 15:04:51]

Scary that this relied on the implicit conversion to bool from the enum.

-                                               http_info->response_time,
-                                               base::Time::Now()) ||
+        base::Time::Now() >= expiration_times.GetFreshnessExpiry() ||
         http_info->headers->EnumerateHeader(&iter, name, &value)) {
       LoadFromNewestCacheFailed(url, response_info);
     } else {
       DCHECK(group_->newest_complete_cache());
       AppCacheEntry* copy_me = group_->newest_complete_cache()->GetEntry(url);
       DCHECK(copy_me);
       DCHECK(copy_me->response_id() == response_id);
 
       AppCache::EntryMap::iterator it = url_file_list_.find(url);
       DCHECK(it != url_file_list_.end());
@@ skipping 217 matching lines @@
   // on this object after we've posted a task to delete ourselves.
   if (group_) {
     group_->SetUpdateAppCacheStatus(AppCacheGroup::IDLE);
     group_ = NULL;
   }
 
   base::MessageLoop::current()->DeleteSoon(FROM_HERE, this);
 }
 
 }  // namespace content