media: Send chrome-cache: frfr on first request.

media/blink/url_index.h

Index: media/blink/url_index.h
diff --git a/media/blink/url_index.h b/media/blink/url_index.h
index bce8727f80a6341e4918e72a28a7967c74779f99..f18d358d8e818fbf4aa6168fe9bbe99045256cc3 100644
--- a/media/blink/url_index.h
+++ b/media/blink/url_index.h
@@ -139,6 +139,9 @@ class MEDIA_BLINK_EXPORT UrlData : public base::RefCounted<UrlData> {
   // Accessor
   blink::WebFrame* frame() const { return frame_; }
 
+  void AddBytesRead(int64_t b) { bytes_read_from_cache_ += b; }
+  int64_t BytesReadFromCache() { return bytes_read_from_cache_; }
+
  protected:
   UrlData(const GURL& url,
           CORSMode cors_mode,
@@ -170,6 +173,9 @@ class MEDIA_BLINK_EXPORT UrlData : public base::RefCounted<UrlData> {
   // Length of resource this url points to. (in bytes)
   int64_t length_;
 
+  // Number of bytes read from this resource.
+  int64_t bytes_read_from_cache_ = 0;
+
   // Does the server support ranges?
   bool range_supported_;