Reland of [ResourceScheduler] Yield after starting several requests

content/browser/loader/resource_scheduler.h

 // 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.
 
 #ifndef CONTENT_BROWSER_LOADER_RESOURCE_SCHEDULER_H_
 #define CONTENT_BROWSER_LOADER_RESOURCE_SCHEDULER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 122 matching lines @@
   Client* GetClient(int child_id, int route_id);
 
   ClientMap client_map_;
   size_t max_num_delayable_requests_;
   RequestSet unowned_requests_;
 
   // True if requests to servers that support priorities (e.g., H2/QUIC) can
   // be delayed.
   bool priority_requests_delayable_;
 
+  // True if the scheduler should yield between several successive calls to
+  // start resource requests.
+  bool yielding_scheduler_enabled_;
+  int max_requests_before_yielding_;
+
   DISALLOW_COPY_AND_ASSIGN(ResourceScheduler);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_LOADER_RESOURCE_SCHEDULER_H_