Add methods for telling V8 how much memory audio/video is using.

media/filters/audio_renderer_algorithm.h

Index: media/filters/audio_renderer_algorithm.h
diff --git a/media/filters/audio_renderer_algorithm.h b/media/filters/audio_renderer_algorithm.h
index 940e7e7b9d7e65848219ed95dbbe90aeec195c62..ba285fad0338dec40c532587a924ea4425854011 100644
--- a/media/filters/audio_renderer_algorithm.h
+++ b/media/filters/audio_renderer_algorithm.h
@@ -69,6 +69,9 @@ class MEDIA_EXPORT AudioRendererAlgorithm {
   // Increase the capacity of |audio_buffer_| if possible.
   void IncreaseQueueCapacity();
 
+  // Returns an estimate of the amount of memory (in bytes) used for frames.
+  int64_t GetMemoryUsage() const;
+
   // Returns the number of frames left in |audio_buffer_|, which may be larger
   // than QueueCapacity() in the event that EnqueueBuffer() delivered more data
   // than |audio_buffer_| was intending to hold.