Send important client side event information to the server.

chrome/browser/sync/protocol/sync.proto

 // Copyright (c) 2011 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.
 //
 // Sync protocol for communication between sync client and server.
 
 // Update proto_value_conversions{.h,.cc,_unittest.cc} if you change
 // any fields in this file.
 
 syntax = "proto2";
 
 option optimize_for = LITE_RUNTIME;
 option retain_unknown_fields = true;
 
 package sync_pb;
 
 import "encryption.proto";
+import "client_debug_info.proto";
 
 // Used for inspecting how long we spent performing operations in different
 // backends. All times must be in millis.
 message ProfilingData {
   optional int64 meta_data_write_time = 1;
   optional int64 file_data_write_time = 2;
   optional int64 user_lookup_time = 3;
   optional int64 meta_data_read_time = 4;
   optional int64 file_data_read_time = 5;
   optional int64 total_request_time = 6;
@@ skipping 403 matching lines @@
   optional CommitMessage commit = 4;
   optional GetUpdatesMessage get_updates = 5;
   optional AuthenticateMessage authenticate = 6;
   // Request to clear all Chromium data from the server
   optional ClearUserDataMessage clear_user_data = 9;
 
   optional string store_birthday = 7; // Opaque store ID; if it changes, duck!
   // The client sets this if it detects a sync issue. The server will tell it
   // if it should perform a refresh.
   optional bool sync_problem_detected = 8 [default = false];
+
+  // Client side state information for debugging purpose.
+  // This is only sent on the first getupdates of every sync cycle,
+  // as an optimization to save bandwidth.
+  optional DebugInfo debug_info = 10;
 };
 
 message CommitResponse {
   enum ResponseType {
     SUCCESS = 1;
     CONFLICT = 2; // You're out of date; update and check your data
     // TODO(ncarter): What's the difference between RETRY and TRANSIENT_ERROR?
     RETRY = 3; // Someone has a conflicting, non-expired session open
     INVALID_MESSAGE = 4; // What the client sent was invalid, and trying again
                          // won't help.
@@ skipping 214 matching lines @@
   optional string store_birthday = 6;
 
   optional ClientCommand client_command = 7;
   optional ProfilingData profiling_data = 8;
 
   // The data types whose storage has been migrated.  Present when the value of
   // error_code is MIGRATION_DONE.
   repeated int32 migrated_data_type_id = 12;
 };