Count total bytes sent in RTPSender::Bytes().

Previously only media bytes were included, this adds header bytes and
padding bytes to the calculation.

BUG=
R=stefan@webrtc.org, tommi@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/19939004

git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@6654 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/common_types.h b/common_types.h
index 193e281..796ddca 100644
--- a/common_types.h
+++ b/common_types.h
@@ -225,6 +225,7 @@
      retransmitted_packets(0),
      fec_packets(0) {}
 
+  // TODO(pbos): Rename bytes -> media_bytes.
   uint32_t bytes;  // Payload bytes, excluding RTP headers and padding.
   uint32_t header_bytes;  // Number of bytes used by RTP headers.
   uint32_t padding_bytes;  // Number of padding bytes.