[Blink-Scheduler] Distinguish between normal and foreground-only renderers for monitoring load.

content/public/renderer/content_renderer_client.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_PUBLIC_RENDERER_CONTENT_RENDERER_CLIENT_H_
 #define CONTENT_PUBLIC_RENDERER_CONTENT_RENDERER_CLIENT_H_
 
 #include <stddef.h>
 
 #include <map>
@@ skipping 344 matching lines @@
   // An empty URL is returned if the URL is not overriden.
   virtual GURL OverrideFlashEmbedWithHTML(const GURL& url);
 
   // Provides parameters for initializing the global task scheduler. Default
   // params are used if this returns nullptr.
   virtual std::unique_ptr<base::TaskScheduler::InitParams>
   GetTaskSchedulerInitParams();
 
   // Returns true if the media pipeline can be suspended, or false otherwise.
   virtual bool AllowMediaSuspend();
+
+  // Returns true if this renderer can be backgrounded.
+  virtual bool CanBeBackgrounded() const;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_RENDERER_CONTENT_RENDERER_CLIENT_H_