Initial implementation of the ByteStream refactor.

net/base/net_log_event_type_list.h

Index: net/base/net_log_event_type_list.h
diff --git a/net/base/net_log_event_type_list.h b/net/base/net_log_event_type_list.h
index 757fb4c79fd8164263be785a1a5f16c697df543c..921a3163ba374e70032da1fe15dd8cbf6479bf54 100644
--- a/net/base/net_log_event_type_list.h
+++ b/net/base/net_log_event_type_list.h
@@ -1575,11 +1575,13 @@ EVENT_TYPE(DOWNLOAD_ITEM_CANCELED)
 //   }
 EVENT_TYPE(DOWNLOAD_FILE_OPENED)
 
-// This event is created when a download file is written to.
+// This event is created when the pipe between download source
+// and download file is drained.
 //   {
-//     "byte_count": <Number of bytes written in this call>,
+//     "pipe_size": <Total size of all bytes drained from the pipe>
+//     "num_buffers": <How many separate buffers those bytes were in>
 //   }
-EVENT_TYPE(DOWNLOAD_FILE_WRITTEN)
+EVENT_TYPE(DOWNLOAD_PIPE_DRAINED)
 
 // This event is created when a download file is renamed.
 //   {