Revert 290359 "Remove AudioBuffersState class."

trunk/src/media/audio/audio_low_latency_input_output_unittest.cc

Index: trunk/src/media/audio/audio_low_latency_input_output_unittest.cc
===================================================================
--- trunk/src/media/audio/audio_low_latency_input_output_unittest.cc	(revision 290374)
+++ trunk/src/media/audio/audio_low_latency_input_output_unittest.cc	(working copy)
@@ -226,14 +226,23 @@
 
   // AudioOutputStream::AudioSourceCallback.
   virtual int OnMoreData(AudioBus* audio_bus,
-                         int total_bytes_delay) OVERRIDE {
+                         AudioBuffersState buffers_state) OVERRIDE {
     base::AutoLock lock(lock_);
 
     // Update one component in the AudioDelayState for the packet
     // which is about to be played out.
     if (output_elements_to_write_ < kMaxDelayMeasurements) {
+      int output_delay_bytes = buffers_state.hardware_delay_bytes;
+#if defined(OS_WIN)
+      // Special fix for Windows in combination with Wave where the
+      // pending bytes field of the audio buffer state is used to
+      // report the delay.
+      if (!CoreAudioUtil::IsSupported()) {
+        output_delay_bytes = buffers_state.pending_bytes;
+      }
+#endif
       delay_states_[output_elements_to_write_].output_delay_ms =
-          BytesToMilliseconds(total_bytes_delay);
+          BytesToMilliseconds(output_delay_bytes);
       ++output_elements_to_write_;
     }