Server push cancellation: add NetLogs to track cache lookup transaction

net/log/net_log_event_type_list.h

Index: net/log/net_log_event_type_list.h
diff --git a/net/log/net_log_event_type_list.h b/net/log/net_log_event_type_list.h
index bfdc0945062aa2c0b5477ed72ecaf358b175a18c..93b64bdfc77d4802af77afa423a37b3590b0c0bb 100644
--- a/net/log/net_log_event_type_list.h
+++ b/net/log/net_log_event_type_list.h
@@ -1303,6 +1303,26 @@ EVENT_TYPE(BIDIRECTIONAL_STREAM_READY)
 EVENT_TYPE(BIDIRECTIONAL_STREAM_FAILED)
 
 // ------------------------------------------------------------------------
+// SERVER_PUSH_LOOKUP_TRANSACTION
+// ------------------------------------------------------------------------
+
+// The start/end of a push lookup transaction for server push.
+//
+// The START event has the parameters:
+//   {
+//     "source_dependency": <Source identifier for the server push lookp.
+//                           It can be a QUIC_SESSION or a HTTP2_SESSION>,
+//     "pushed_url": <The url that has been pushed and looked up>,
+//   }
+//
+// If the transaction doesn't find the resource in cache, then the END phase
+// has these parameters:
+//   {
+//     "net_error": <Net error code integer>,
+//   }
+EVENT_TYPE(SERVER_PUSH_LOOKUP_TRANSACTION)
+
+// ------------------------------------------------------------------------
 // SpdySession
 // ------------------------------------------------------------------------