Implement SetDefersLoading on content::URLLoaderClientImpl

content/child/resource_dispatcher.cc

Index: content/child/resource_dispatcher.cc
diff --git a/content/child/resource_dispatcher.cc b/content/child/resource_dispatcher.cc
index 3cbc9ff68c4277c46935b2f1bbe7f4f1c56c3019..cf5d047bc4cbeccc6b9e1a42b595719f578e8353 100644
--- a/content/child/resource_dispatcher.cc
+++ b/content/child/resource_dispatcher.cc
@@ -483,9 +483,14 @@ void ResourceDispatcher::SetDefersLoading(int request_id, bool value) {
   }
   if (value) {
     request_info->is_deferred = value;
+    if (request_info->url_loader_client)
+      request_info->url_loader_client->SetDefersLoading();
   } else if (request_info->is_deferred) {
     request_info->is_deferred = false;
 
+    if (request_info->url_loader_client)
+      request_info->url_loader_client->UnsetDefersLoading();
+
     FollowPendingRedirect(request_id, request_info);
 
     main_thread_task_runner_->PostTask(
@@ -553,6 +558,10 @@ void ResourceDispatcher::FlushDeferredMessages(int request_id) {
   PendingRequestInfo* request_info = GetPendingRequestInfo(request_id);
   if (!request_info || request_info->is_deferred)
     return;
+
+  if (request_info->url_loader)
+    request_info->url_loader_client->FlushDeferredMessages();

[kinuko, 2016/12/23 13:11:23]

Having two pending queues is confusing, it seems if we have url_loader should
resource_dispatcher's deferred_message_queue is empty, is that right?  If so
could we DCHECK it and return here?

[yhirano, 2016/12/26 05:08:35]

I've just noticed that |request_info| can be broken here (i.e., the cancelled
case). So I'm simply putting a return statement here.

+
   // Because message handlers could result in request_info being destroyed,
   // we need to work with a stack reference to the deferred queue.
   MessageQueue q;