media::SilentSinkSuspender should simulate |delay| and |delay_timestamp|

media/base/fake_audio_render_callback.h

 // Copyright (c) 2012 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 MEDIA_BASE_FAKE_AUDIO_RENDER_CALLBACK_H_
 #define MEDIA_BASE_FAKE_AUDIO_RENDER_CALLBACK_H_
 
 #include <stdint.h>
 
 #include "base/macros.h"
 #include "media/base/audio_converter.h"
 #include "media/base/audio_renderer_sink.h"
 #include "testing/gmock/include/gmock/gmock.h"
 
 namespace media {
 
 // Fake RenderCallback which will fill each request with a sine wave.  Sine
 // state is kept across callbacks.  State can be reset to default via reset().
 // Also provide an interface to AudioTransformInput.
 class FakeAudioRenderCallback
     : public AudioRendererSink::RenderCallback,
       public AudioConverter::InputCallback {
  public:
   // The function used to fulfill Render() is f(x) = sin(2 * PI * x * |step|),
   // where x = [|number_of_frames| * m, |number_of_frames| * (m + 1)] and m =
   // the number of Render() calls fulfilled thus far.
-  explicit FakeAudioRenderCallback(double step);
+  FakeAudioRenderCallback(double step, int sample_rate);
   ~FakeAudioRenderCallback() override;
 
   // Renders a sine wave into the provided audio data buffer.  If |half_fill_|
   // is set, will only fill half the buffer.
   int Render(base::TimeDelta delay,
              base::TimeTicks delay_timestamp,
              int prior_frames_skipped,
              AudioBus* audio_bus) override;
   MOCK_METHOD0(OnRenderError, void());
 
   // AudioTransform::ProvideAudioTransformInput implementation.
   double ProvideInput(AudioBus* audio_bus, uint32_t frames_delayed) override;
 
   // Toggles only filling half the requested amount during Render().
   void set_half_fill(bool half_fill) { half_fill_ = half_fill; }
 
   // Reset the sine state to initial value.
   void reset() { x_ = 0; }
 
-  // Returns the last |frames_delayed| provided to Render() or -1 if
-  // no Render() call occurred.
-  int last_frames_delayed() const { return last_frames_delayed_; }
+  // Returns the last |delay| provided to Render() or base::TimeDelta::Max()
+  // if no Render() call occurred.
+  base::TimeDelta last_delay() const { return last_delay_; }
 
   // Set volume information used by ProvideAudioTransformInput().
   void set_volume(double volume) { volume_ = volume; }
 
   int last_channel_count() const { return last_channel_count_; }
 
  private:
-  int RenderInternal(AudioBus* audio_bus,
-                     uint32_t frames_delayed,
-                     double volume);
+  int RenderInternal(AudioBus* audio_bus, base::TimeDelta delay, double volume);
 
   bool half_fill_;
   double x_;
   double step_;
-  int last_frames_delayed_;
+  base::TimeDelta last_delay_;
   int last_channel_count_;
   double volume_;
+  int sample_rate_;
 
   DISALLOW_COPY_AND_ASSIGN(FakeAudioRenderCallback);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_FAKE_AUDIO_RENDER_CALLBACK_H_