[scheduler] Teach scheduler about audio state

content/browser/media/audio_stream_monitor.cc

 // 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.
 
 #include "content/browser/media/audio_stream_monitor.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/public/browser/browser_thread.h"
@@ skipping 133 matching lines @@
 
     if (power_dbfs >= kSilenceThresholdDBFS) {
       last_blurt_time_ = clock_->NowTicks();
       is_audible_ = true;
       MaybeToggle();
       break;  // No need to poll remaining streams.
     }
   }
 
   if (is_audible_ != was_audible)
-    web_contents_->NotifyNavigationStateChanged(INVALIDATE_TYPE_TAB);
+    web_contents_->OnAudioStateChanged(is_audible_);
 }
 
 void AudioStreamMonitor::MaybeToggle() {
   const bool indicator_was_on = was_recently_audible_;
   const base::TimeTicks off_time =
       last_blurt_time_ + base::TimeDelta::FromMilliseconds(kHoldOnMilliseconds);
   const base::TimeTicks now = clock_->NowTicks();
   const bool should_indicator_be_on = now < off_time;
 
   if (should_indicator_be_on != indicator_was_on) {
     was_recently_audible_ = should_indicator_be_on;
     web_contents_->NotifyNavigationStateChanged(INVALIDATE_TYPE_TAB);
   }
 
   if (!should_indicator_be_on) {
     off_timer_.Stop();
   } else if (!off_timer_.IsRunning()) {
     off_timer_.Start(
         FROM_HERE,
         off_time - now,
         base::Bind(&AudioStreamMonitor::MaybeToggle, base::Unretained(this)));
   }
 }
 
 }  // namespace content