Remove redundant definition of Spatializer abstract class

third_party/WebKit/Source/platform/audio/Spatializer.h

-// 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.
-
-#ifndef Spatializer_h
-#define Spatializer_h
-
-#include "platform/PlatformExport.h"
-#include "wtf/Allocator.h"
-#include "wtf/Noncopyable.h"
-#include <memory>
-
-namespace blink {
-
-class AudioBus;
-
-// Abstract base class for spatializing a mono or stereo source.
-class PLATFORM_EXPORT Spatializer {
-    USING_FAST_MALLOC(Spatializer);
-    WTF_MAKE_NONCOPYABLE(Spatializer);
-public:
-    enum {
-        PanningModelEqualPower = 0
-
-        // We have a plan to add more panning models other than equal-power.
-        // (such as binaural-HRTF or N-channel surround panning)
-    };
-
-    typedef unsigned PanningModel;
-
-    static std::unique_ptr<Spatializer> create(PanningModel, float sampleRate);
-    virtual ~Spatializer();
-
-    // Handle sample-accurate panning by AudioParam automation.
-    virtual void panWithSampleAccurateValues(const AudioBus* inputBus, AudioBus* outputBuf, const float* panValues, size_t framesToProcess) = 0;
-
-    // Handle de-zippered panning to a target value.
-    virtual void panToTargetValue(const AudioBus* inputBus, AudioBus* outputBuf, float panValue, size_t framesToProcess) = 0;
-
-    virtual void reset() = 0;
-    virtual double tailTime() const = 0;
-    virtual double latencyTime() const = 0;
-
-protected:
-    explicit Spatializer(PanningModel model) { }
-};
-
-} // namespace blink
-
-#endif // Spatializer_h