Extending supported sample rate from 3.0KHz to 192.0KHz for OfflineAudioContext.

Source/modules/webaudio/AudioContext.cpp

 /*
  * 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
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@@ skipping 62 matching lines @@
 #include "wtf/PassOwnPtr.h"
 #include "wtf/text/WTFString.h"
 
 // FIXME: check the proper way to reference an undefined thread ID
 const int UndefinedThreadIdentifier = 0xffffffff;
 
 namespace WebCore {
 
 bool AudioContext::isSampleRateRangeGood(float sampleRate)
 {
-    // FIXME: It would be nice if the minimum sample-rate could be less than 44.1KHz,
-    // but that will require some fixes in HRTFPanner::fftSizeForSampleRate(), and some testing there.
-    return sampleRate >= 44100 && sampleRate <= 96000;
+    return sampleRate >= 8000 && sampleRate <= 96000;

[Raymond Toy, 2014/07/30 16:49:38]

AudioBuffers support sample rates from 3kHz to 192 kHz. I think offline contexts
should support the same range.

[KhNo, 2014/07/31 16:45:53]

I think there is no reason we should hesitate to extend range. It should have
same range with AudioBuffers.

[Raymond Toy, 2014/07/31 17:25:13]

Great. Then you can use AudioBuffer::minSampleRate and maxSampleRate to get the
limits.

 }
 
 // Don't allow more than this number of simultaneous AudioContexts talking to hardware.
 const unsigned MaxHardwareContexts = 6;
 unsigned AudioContext::s_hardwareContextCount = 0;
 
 PassRefPtrWillBeRawPtr<AudioContext> AudioContext::create(Document& document, ExceptionState& exceptionState)
 {
     ASSERT(isMainThread());
     if (s_hardwareContextCount >= MaxHardwareContexts) {
@@ skipping 859 matching lines @@
     visitor->trace(m_renderTarget);
     visitor->trace(m_destinationNode);
     visitor->trace(m_listener);
     visitor->trace(m_dirtySummingJunctions);
     EventTargetWithInlineData::trace(visitor);
 }
 
 } // namespace WebCore
 
 #endif // ENABLE(WEB_AUDIO)