Rename sequence_number to timestamp.

remoting/proto/internal.proto

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Internal message types that should not be seen outside the protocol
 // directory.
 
 syntax = "proto2";
 
 import "control.proto";
@@ skipping 11 matching lines @@
   optional VideoControl video_control = 3;
   optional AudioControl audio_control = 5;
   optional Capabilities capabilities = 6;
   optional PairingRequest pairing_request = 7;
   optional PairingResponse pairing_response = 8;
   optional ExtensionMessage extension_message = 9;
 }
 
 // Defines an event message on the event channel.
 message EventMessage {
-  optional int64 sequence_number = 1;  // Client timestamp for event.
+  // Client's timestamp used to estimate roundtrip latency.
+  optional int64 timestamp = 1;
 
   optional KeyEvent key_event = 3;
   optional MouseEvent mouse_event = 4;
   optional TextEvent text_event = 5;
 }