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diff --git a/chromium/third_party/blink/renderer/platform/scheduler/main_thread/main_thread_web_scheduling_task_queue_impl.h b/chromium/third_party/blink/renderer/platform/scheduler/main_thread/main_thread_web_scheduling_task_queue_impl.h
new file mode 100644
index 00000000000..33ac23e160c
--- /dev/null
+++ b/chromium/third_party/blink/renderer/platform/scheduler/main_thread/main_thread_web_scheduling_task_queue_impl.h
@@ -0,0 +1,69 @@
+// Copyright 2019 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 THIRD_PARTY_BLINK_RENDERER_PLATFORM_SCHEDULER_MAIN_THREAD_MAIN_THREAD_WEB_SCHEDULING_TASK_QUEUE_IMPL_H_
+#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_SCHEDULER_MAIN_THREAD_MAIN_THREAD_WEB_SCHEDULING_TASK_QUEUE_IMPL_H_
+
+#include "third_party/blink/renderer/platform/scheduler/public/web_scheduling_task_queue.h"
+
+#include "base/memory/scoped_refptr.h"
+#include "base/memory/weak_ptr.h"
+#include "base/single_thread_task_runner.h"
+#include "third_party/blink/renderer/platform/platform_export.h"
+#include "third_party/blink/renderer/platform/scheduler/public/web_scheduling_priority.h"
+
+namespace blink {
+namespace scheduler {
+
+class MainThreadTaskQueue;
+
+class PLATFORM_EXPORT MainThreadWebSchedulingTaskQueueImpl
+    : public WebSchedulingTaskQueue {
+ public:
+  MainThreadWebSchedulingTaskQueueImpl(
+      base::WeakPtr<MainThreadTaskQueue> immediate_task_queue,
+      base::WeakPtr<MainThreadTaskQueue> delayed_task_queue);
+  ~MainThreadWebSchedulingTaskQueueImpl() override;
+
+  void SetPriority(WebSchedulingPriority) override;
+
+  scoped_refptr<base::SingleThreadTaskRunner> GetTaskRunner() override;
+
+ private:
+  // In order to throttle delayed tasks in the background, we manage two
+  // MainThreadTaskQueues and their associated TaskRunners---one for delayed
+  // tasks and one for non-delayed tasks (immediate). Rather than exposing this
+  // to the web scheduling layer, we implement a simple custom TaskRunner that
+  // handles picking the appropriate underlying TaskRunner based on the delay
+  // value and return that in GetTaskRunner().
+  class WebSchedulingTaskRunner : public base::SingleThreadTaskRunner {
+   public:
+    WebSchedulingTaskRunner(
+        scoped_refptr<base::SingleThreadTaskRunner> immediate_task_runner,
+        scoped_refptr<base::SingleThreadTaskRunner> delayed_task_runner);
+
+    bool PostDelayedTask(const base::Location& location,
+                         base::OnceClosure task,
+                         base::TimeDelta delay) override;
+    bool PostNonNestableDelayedTask(const base::Location& from_here,
+                                    base::OnceClosure task,
+                                    base::TimeDelta delay) override;
+    bool RunsTasksInCurrentSequence() const override;
+
+   private:
+    base::SingleThreadTaskRunner* GetTaskRunnerForDelay(base::TimeDelta delay);
+
+    const scoped_refptr<base::SingleThreadTaskRunner> immediate_task_runner_;
+    const scoped_refptr<base::SingleThreadTaskRunner> delayed_task_runner_;
+  };
+
+  scoped_refptr<WebSchedulingTaskRunner> task_runner_;
+  base::WeakPtr<MainThreadTaskQueue> immediate_task_queue_;
+  base::WeakPtr<MainThreadTaskQueue> delayed_task_queue_;
+};
+
+}  // namespace scheduler
+}  // namespace blink
+
+#endif  // THIRD_PARTY_BLINK_RENDERER_PLATFORM_SCHEDULER_MAIN_THREAD_MAIN_THREAD_WEB_SCHEDULING_TASK_QUEUE_IMPL_H_