Forward the number of skipped frames by the OS in audio playout.

media/audio/audio_parameters.h

Index: media/audio/audio_parameters.h
diff --git a/media/audio/audio_parameters.h b/media/audio/audio_parameters.h
index c59dd30885e36672cde8eb6e1a2086ac3e94a2ee..f93688104d7a05b848942142f953bd7603b3b1a2 100644
--- a/media/audio/audio_parameters.h
+++ b/media/audio/audio_parameters.h
@@ -19,25 +19,28 @@
 namespace media {
 
 // Use a struct-in-struct approach to ensure that we can calculate the required
-// size as sizeof(AudioInputBufferParameters) + #(bytes in audio buffer) without
-// using packing. Also align AudioInputBufferParameters instead of in
-// AudioInputBuffer to be able to calculate size like so. Use a macro for the
-// alignment value that's the same as AudioBus::kChannelAlignment, since MSVC
-// doesn't accept the latter to be used.
+// size as sizeof(Audio{Input,Output}BufferParameters) + #(bytes in audio
+// buffer) without using packing. Also align Audio{Input,Output}BufferParameters
+// instead of in Audio{Input,Output}Buffer to be able to calculate size like so.
+// Use a macro for the alignment value that's the same as
+// AudioBus::kChannelAlignment, since MSVC doesn't accept the latter to be used.
 #if defined(OS_WIN)
 #pragma warning(push)
 #pragma warning(disable: 4324)  // Disable warning for added padding.
 #endif
 #define PARAMETERS_ALIGNMENT 16
 static_assert(AudioBus::kChannelAlignment == PARAMETERS_ALIGNMENT,
-              "AudioInputBufferParameters alignment not same as AudioBus");
+              "Audio buffer parameters struct alignment not same as AudioBus");
 struct MEDIA_EXPORT ALIGNAS(PARAMETERS_ALIGNMENT) AudioInputBufferParameters {
   double volume;
-  uint32 size;
+  uint32_t size;
   uint32_t hardware_delay_bytes;
   uint32_t id;
   bool key_pressed;
 };
+struct MEDIA_EXPORT ALIGNAS(PARAMETERS_ALIGNMENT) AudioOutputBufferParameters {
+  uint32_t frames_skipped;
+};
 #undef PARAMETERS_ALIGNMENT
 #if defined(OS_WIN)
 #pragma warning(pop)
@@ -47,11 +50,19 @@ static_assert(sizeof(AudioInputBufferParameters) %
                       AudioBus::kChannelAlignment ==
                   0,
               "AudioInputBufferParameters not aligned");
+static_assert(sizeof(AudioOutputBufferParameters) %
+                      AudioBus::kChannelAlignment ==
+                  0,
+              "AudioOutputBufferParameters not aligned");
 
 struct MEDIA_EXPORT AudioInputBuffer {
   AudioInputBufferParameters params;
   int8 audio[1];
 };
+struct MEDIA_EXPORT AudioOutputBuffer {
+  AudioOutputBufferParameters params;
+  int8 audio[1];
+};
 
 class MEDIA_EXPORT AudioParameters {
  public: