[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 43 matching lines @@
 
         // In this policy virtual time is allowed to advance unless there are 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 isPlayingAudio) = 0;
 };
 
 } // namespace blink
 
 #endif // WebViewScheduler