Revert "Fix race on demuxer memory usage. Reuse previous calculation."

media/base/demuxer.h

Index: media/base/demuxer.h
diff --git a/media/base/demuxer.h b/media/base/demuxer.h
index 2324c87ab16685617720ed09dd903f640c23bb87..1f136a0cbcccd6e93f1ad85804407c9ecb1a4d04 100644
--- a/media/base/demuxer.h
+++ b/media/base/demuxer.h
@@ -87,8 +87,7 @@ class MEDIA_EXPORT Demuxer : public DemuxerStreamProvider {
   // a null Time is returned.
   virtual base::Time GetTimelineOffset() const = 0;
 
-  // Returns the memory usage in bytes for the demuxer. May be called from any
-  // thread.
+  // Returns the memory usage in bytes for the demuxer.
   virtual int64_t GetMemoryUsage() const = 0;
 
  private: