[scheduler] Teach scheduler about audio state

content/public/browser/web_contents.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_BROWSER_WEB_CONTENTS_H_
 #define CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_H_
 
 #include <stdint.h>
 
 #include <set>
@@ skipping 389 matching lines @@
   virtual base::TerminationStatus GetCrashedStatus() const = 0;
   virtual int GetCrashedErrorCode() const = 0;
 
   // Whether the tab is in the process of being destroyed.
   virtual bool IsBeingDestroyed() const = 0;
 
   // Convenience method for notifying the delegate of a navigation state
   // change.
   virtual void NotifyNavigationStateChanged(InvalidateTypes changed_flags) = 0;
 
+  // Notifies the WebContents that audio started or stopped being audible.
+  virtual void OnAudioStateChanged(bool is_audio_playing) = 0;
+
   // Get/Set the last time that the WebContents was made active (either when it
   // was created or shown with WasShown()).
   virtual base::TimeTicks GetLastActiveTime() const = 0;
   virtual void SetLastActiveTime(base::TimeTicks last_active_time) = 0;
 
   // Invoked when the WebContents becomes shown/hidden.
   virtual void WasShown() = 0;
   virtual void WasHidden() = 0;
 
   // Returns true if the before unload and unload listeners need to be
@@ skipping 331 matching lines @@
 
  private:
   // This interface should only be implemented inside content.
   friend class WebContentsImpl;
   WebContents() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_H_