Move DataSource::SetPreload() to BufferedDataSource.

media/base/data_source.h

Index: media/base/data_source.h
diff --git a/media/base/data_source.h b/media/base/data_source.h
index 75772373ed7f5b8f84f3d7c4d7522dd8437f11c1..3b51f3fff5c09f88a7d44bcf4afa2030195258e8 100644
--- a/media/base/data_source.h
+++ b/media/base/data_source.h
@@ -8,7 +8,6 @@
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "media/base/media_export.h"
-#include "media/base/preload.h"
 
 namespace media {
 
@@ -61,9 +60,6 @@ class MEDIA_EXPORT DataSource : public base::RefCountedThreadSafe<DataSource> {
   // not possible.
   virtual bool IsStreaming() = 0;
 
-  // Alert the DataSource that the video preload value has been changed.
-  virtual void SetPreload(Preload preload) = 0;
-
   // Notify the DataSource of the bitrate of the media.
   // Values of |bitrate| <= 0 are invalid and should be ignored.
   virtual void SetBitrate(int bitrate) = 0;