| Index: media/base/audio_timestamp_helper.cc
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| diff --git a/media/base/audio_timestamp_helper.cc b/media/base/audio_timestamp_helper.cc
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| index 8429a3eb81ea0eb4336b5ef550b4906101c60237..8694ae329a003aed933cccba44429941c7305457 100644
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| --- a/media/base/audio_timestamp_helper.cc
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| +++ b/media/base/audio_timestamp_helper.cc
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| @@ -9,6 +9,20 @@
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|  
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|  namespace media {
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|  
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| +// static
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| +base::TimeDelta AudioTimestampHelper::FramesToTime(int64_t frames,
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| +                                                   int samples_per_second) {
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| +  DCHECK_GE(samples_per_second, 0);
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| +  return base::TimeDelta::FromMicroseconds(
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| +      frames * base::Time::kMicrosecondsPerSecond / samples_per_second);
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| +}
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| +
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| +// static
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| +int64_t AudioTimestampHelper::TimeToFrames(base::TimeDelta time,
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| +                                           int samples_per_second) {
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| +  return time.InSecondsF() * samples_per_second;
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| +}
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| +
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|  AudioTimestampHelper::AudioTimestampHelper(int samples_per_second)
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|      : base_timestamp_(kNoTimestamp), frame_count_(0) {
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|    DCHECK_GT(samples_per_second, 0);
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| 
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