BufferedDataSource now caches redirects for subsequent requests

media/blink/buffered_data_source.cc

 // Copyright 2013 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 "media/blink/buffered_data_source.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
@@ skipping 369 matching lines @@
 
   bool init_cb_is_null = false;
   {
     base::AutoLock auto_lock(lock_);
     init_cb_is_null = init_cb_.is_null();
   }
   if (init_cb_is_null) {
     loader_->Stop();
     return;
   }
+
   response_original_url_ = loader_->response_original_url();
+  // The response original url is the URL of this resource after following
+  // redirects. Update |url_| to this so that we only follow redirects once for
+  // simplicity and efficiency.
+  // If it's empty, it was a response from a Service Worker, so keep the

[hubbe, 2016/04/28 19:34:17]

Why do we care if it's a service worker?

[watk, 2016/04/28 20:05:16]

I guess my phrasing is slightly misleading. It's not that it was a service
worker that's important, but that it's empty. The only reason I mentioned
Service Workers is because otherwise it's not obvious why we'd check for an
empty url.

Should I reword it?

+  // original URL.
+  if (!response_original_url_.is_empty())
+    url_ = response_original_url_;
 
   // All responses must be successful. Resources that are assumed to be fully
   // buffered must have a known content length.
   bool success = status == BufferedResourceLoader::kOk &&
                  (!assume_fully_buffered() ||
                   loader_->instance_size() != kPositionNotSpecified);
 
   if (success) {
     total_bytes_ = loader_->instance_size();
     streaming_ =
@@ skipping 207 matching lines @@
   }
 
   // If media is currently playing or the page indicated preload=auto or the
   // the server does not support the byte range request or we do not want to go
   // too far ahead of the read head, use threshold strategy to enable/disable
   // deferring when the buffer is full/depleted.
   loader_->UpdateDeferStrategy(BufferedResourceLoader::kCapacityDefer);
 }
 
 }  // namespace media