Continue to process AnalyserNode if inputs are silent.

third_party/WebKit/Source/modules/webaudio/AnalyserNode.h

 /*
  * Copyright (C) 2010, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 57 matching lines @@
   void getByteFrequencyData(DOMUint8Array* array, double currentTime) {
     m_analyser.getByteFrequencyData(array, currentTime);
   }
   void getFloatTimeDomainData(DOMFloat32Array* array) {
     m_analyser.getFloatTimeDomainData(array);
   }
   void getByteTimeDomainData(DOMUint8Array* array) {
     m_analyser.getByteTimeDomainData(array);
   }
 
+  // AnalyserNode needs special handling when updating the pull status
+  // because the node must get pulled even if there are no inputs or
+  // outputs so that the internal state is properly updated with the
+  // correct time data.
+  void updatePullStatus() override;
+
  private:
   AnalyserHandler(AudioNode&, float sampleRate);
+  bool propagatesSilence() const {
+    // An AnalyserNode does actually propogate silence, but to get the
+    // time and FFT data updated correctly, process() needs to be
+    // called even if all the inputs are silent.
+    return false;
+  }
 
   RealtimeAnalyser m_analyser;
 };
 
 class AnalyserNode final : public AudioBasicInspectorNode {
   DEFINE_WRAPPERTYPEINFO();
 
  public:
   static AnalyserNode* create(BaseAudioContext&, ExceptionState&);
   static AnalyserNode* create(BaseAudioContext*,
@@ skipping 17 matching lines @@
  private:
   AnalyserNode(BaseAudioContext&);
   AnalyserHandler& analyserHandler() const;
 
   void setMinMaxDecibels(double min, double max, ExceptionState&);
 };
 
 }  // namespace blink
 
 #endif  // AnalyserNode_h