Implementation of 'AudioContext.getOutputTimestamp' method

media/audio/audio_output_resampler.cc

Index: media/audio/audio_output_resampler.cc
diff --git a/media/audio/audio_output_resampler.cc b/media/audio/audio_output_resampler.cc
index c643b3e672c24ed086c07bf5d19262d396b66697..eef9da5ae120416b127ddd864affd863ae6c257d 100644
--- a/media/audio/audio_output_resampler.cc
+++ b/media/audio/audio_output_resampler.cc
@@ -33,7 +33,8 @@ class OnMoreDataConverter
   // AudioSourceCallback interface.
   int OnMoreData(AudioBus* dest,
                  uint32_t total_bytes_delay,
-                 uint32_t frames_skipped) override;
+                 uint32_t frames_skipped,
+                 const AudioTimestamp& timestamp) override;
   void OnError(AudioOutputStream* stream) override;
 
   // Sets |source_callback_|.  If this is not a new object, then Stop() must be
@@ -72,6 +73,9 @@ class OnMoreDataConverter
   // stream has been stopped.
   bool error_occurred_;
 
+  // Information about last recorded stream output position.
+  AudioTimestamp output_timestamp_;
+
   DISALLOW_COPY_AND_ASSIGN(OnMoreDataConverter);
 };
 
@@ -348,7 +352,8 @@ OnMoreDataConverter::OnMoreDataConverter(const AudioParameters& input_params,
       source_callback_(nullptr),
       input_bytes_per_frame_(input_params.GetBytesPerFrame()),
       audio_converter_(input_params, output_params, false),
-      error_occurred_(false) {}
+      error_occurred_(false),
+      output_timestamp_() {}
 
 OnMoreDataConverter::~OnMoreDataConverter() {
   // Ensure Stop() has been called so we don't end up with an AudioOutputStream
@@ -375,7 +380,9 @@ void OnMoreDataConverter::Stop() {
 
 int OnMoreDataConverter::OnMoreData(AudioBus* dest,
                                     uint32_t total_bytes_delay,
-                                    uint32_t frames_skipped) {
+                                    uint32_t frames_skipped,
+                                    const AudioTimestamp& timestamp) {
+  output_timestamp_ = timestamp;
   current_total_bytes_delay_ = total_bytes_delay;
   audio_converter_.Convert(dest);
 
@@ -394,8 +401,8 @@ double OnMoreDataConverter::ProvideInput(AudioBus* dest,
       (current_total_bytes_delay_ + frames_delayed * input_bytes_per_frame_));
 
   // Retrieve data from the original callback.
-  const int frames =
-      source_callback_->OnMoreData(dest, new_total_bytes_delay, 0);
+  const int frames = source_callback_->OnMoreData(dest, new_total_bytes_delay,
+                                                  0, output_timestamp_);
 
   // Zero any unfilled frames if anything was filled, otherwise we'll just
   // return a volume of zero and let AudioConverter drop the output.