Add support for fallback content for the frame. This includes main and subframes.

content/common/throttling_url_loader.cc

 // Copyright 2017 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/common/throttling_url_loader.h"
 
 #include "base/single_thread_task_runner.h"
 
 namespace content {
 
@@ skipping 85 matching lines @@
   if (!url_loader_ && !cancelled_by_throttle_) {
     DCHECK_EQ(DEFERRED_START, deferred_stage_);
     priority_info_ =
         base::MakeUnique<PriorityInfo>(priority, intra_priority_value);
     return;
   }
 
   url_loader_->SetPriority(priority, intra_priority_value);
 }
 
+void ThrottlingURLLoader::DisconnectClient() {
+  client_binding_.Close();
+  url_loader_ = nullptr;
+}
+
 ThrottlingURLLoader::ThrottlingURLLoader(
     std::vector<std::unique_ptr<URLLoaderThrottle>> throttles,
     mojom::URLLoaderClient* client,
     const net::NetworkTrafficAnnotationTag& traffic_annotation)
     : forwarding_client_(client),
       client_binding_(this),
       traffic_annotation_(traffic_annotation) {
   if (throttles.size() > 0) {
     // TODO(yzshen): Implement a URLLoaderThrottle subclass which handles a list
     // of URLLoaderThrottles.
@@ skipping 172 matching lines @@
   if (cancelled_by_throttle_)
     return;
 
   cancelled_by_throttle_ = true;
 
   ResourceRequestCompletionStatus request_complete_data;
   request_complete_data.error_code = error_code;
   request_complete_data.completion_time = base::TimeTicks::Now();
 
   deferred_stage_ = DEFERRED_NONE;
-  client_binding_.Close();
-  url_loader_ = nullptr;
-
+  DisconnectClient();
   forwarding_client_->OnComplete(request_complete_data);
 }
 
 void ThrottlingURLLoader::Resume() {
   if (cancelled_by_throttle_ || deferred_stage_ == DEFERRED_NONE)
     return;
 
   switch (deferred_stage_) {
     case DEFERRED_START: {
       StartNow(start_info_->url_loader_factory, start_info_->routing_id,
@@ skipping 22 matching lines @@
       break;
     }
     default:
       NOTREACHED();
       break;
   }
   deferred_stage_ = DEFERRED_NONE;
 }
 
 }  // namespace content