[scheduler] Teach scheduler about audio state

third_party/WebKit/public/platform/WebViewScheduler.h

 // Copyright 2015 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 WebViewScheduler_h
 #define WebViewScheduler_h
 
 #include "WebCommon.h"
 #include "public/platform/BlameContext.h"
 
@@ skipping 47 matching lines @@
     // pending network fetches associated any child WebFrameScheduler, or a
     // document is being parsed on a background thread. Initially virtual time
     // is not allowed to advance until we have seen at least one load. The aim
     // being to try and make loading (more) deterministic.
     DETERMINISTIC_LOADING
   };
 
   // Sets the virtual time policy, which is applied imemdiatly to all child
   // WebFrameSchedulers.
   virtual void setVirtualTimePolicy(VirtualTimePolicy) = 0;
+
+  virtual void audioStateChanged(bool isAudioPlaying) = 0;
 };
 
 }  // namespace blink
 
 #endif  // WebViewScheduler