Record accuracy of expected queueing time metric.

third_party/WebKit/public/platform/scheduler/renderer/renderer_scheduler.h

 // Copyright 2014 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_WEBKIT_PUBLIC_PLATFORM_SCHEDULER_RENDERER_RENDERER_SCHEDULER_H_
 #define THIRD_PARTY_WEBKIT_PUBLIC_PLATFORM_SCHEDULER_RENDERER_RENDERER_SCHEDULER_H_
 
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 91 matching lines @@
   virtual void DidHandleInputEventOnCompositorThread(
       const WebInputEvent& web_input_event,
       InputEventState event_state) = 0;
 
   // Tells the scheduler that the system processed an input event. Must be
   // called from the main thread.
   virtual void DidHandleInputEventOnMainThread(
       const WebInputEvent& web_input_event,
       WebInputEventResult result) = 0;
 
+  // Returns the most recently reported expected queueing time, computed over
+  // the past 1 second window.
+  virtual base::TimeDelta MostRecentExpectedQueueingTime() = 0;
+
   // Tells the scheduler that the system is displaying an input animation (e.g.
   // a fling). Called by the compositor (impl) thread.
   virtual void DidAnimateForInputOnCompositorThread() = 0;
 
   // Tells the scheduler about the change of renderer visibility status (e.g.
   // "all widgets are hidden" condition). Used mostly for metric purposes.
   // Must be called on the main thread.
   virtual void SetRendererHidden(bool hidden) = 0;
 
   // Tells the scheduler about the change of renderer background status, i.e.,
@@ skipping 81 matching lines @@
 
  protected:
   RendererScheduler();
   DISALLOW_COPY_AND_ASSIGN(RendererScheduler);
 };
 
 }  // namespace scheduler
 }  // namespace blink
 
 #endif  // THIRD_PARTY_WEBKIT_PUBLIC_PLATFORM_SCHEDULER_RENDERER_RENDERER_SCHEDULER_H_