Convert MediaLog from being ref counted to owned by WebMediaPlayer.

media/formats/webm/webm_content_encodings_client.cc

Index: media/formats/webm/webm_content_encodings_client.cc
diff --git a/media/formats/webm/webm_content_encodings_client.cc b/media/formats/webm/webm_content_encodings_client.cc
index 82dbd60f094212dbaa117b41331193a2d0ad9f66..105a491827f5818f0e49c51a5dee6b3a806d42ab 100644
--- a/media/formats/webm/webm_content_encodings_client.cc
+++ b/media/formats/webm/webm_content_encodings_client.cc
@@ -9,12 +9,10 @@
 
 namespace media {
 
-WebMContentEncodingsClient::WebMContentEncodingsClient(
-    const scoped_refptr<MediaLog>& media_log)
+WebMContentEncodingsClient::WebMContentEncodingsClient(MediaLog* media_log)
     : media_log_(media_log),
       content_encryption_encountered_(false),
-      content_encodings_ready_(false) {
-}
+      content_encodings_ready_(false) {}
 
 WebMContentEncodingsClient::~WebMContentEncodingsClient() {
 }