Audio output debug recording.

media/audio/audio_file_writer.h

Index: media/audio/audio_file_writer.h
diff --git a/media/audio/audio_file_writer.h b/media/audio/audio_file_writer.h
index dabfa23dd95566b78e32f34e6312a5608a9a2b9d..99a6feaff3827539fe071744b832c7ca338021d9 100644
--- a/media/audio/audio_file_writer.h
+++ b/media/audio/audio_file_writer.h
@@ -7,18 +7,23 @@
 
 #include <memory>
 
-namespace base {
-class FilePath;
-}
+#include "base/callback_forward.h"
+#include "base/files/file_path.h"
 
 namespace media {
 
 class AudioBus;
+class AudioParameters;
 
 // A writer interface used for writing audio data to file for debugging
 // purposes.
 class AudioFileWriter {
  public:
+  // Used for creating an AudioFileWriter.
+  using CreateCallback =
+      base::RepeatingCallback<std::unique_ptr<AudioFileWriter>(
+          const AudioParameters&)>;
+
   virtual ~AudioFileWriter() {}
 
   // Must be called before calling Write() for the first time after creation or
@@ -38,8 +43,13 @@ class AudioFileWriter {
   // may be ambigulous if Start() or Stop() is executed at the moment. Can be
   // called from any sequence.
   virtual bool WillWrite() = 0;
+
+  // Gets the extension for the file type the as a string, for example "wav".
+  // Can be called before calling Start() to add the appropriate extension to
+  // the filename.
+  virtual const base::FilePath::CharType* GetFileNameExtension() = 0;
 };
 
-}  // namespace media
+}  // namspace media
 
 #endif  // MEDIA_AUDIO_AUDIO_FILE_WRITER_H_