sync: use progress markers instead of timestamps during GetUpdates

chrome/browser/sync/sessions/session_state.cc

 // Copyright (c) 2009 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.
 
 #include "chrome/browser/sync/sessions/session_state.h"
 
 #include <set>
 #include <vector>
 
 using std::set;
 using std::vector;
 
 namespace browser_sync {
 namespace sessions {
 
 SyncSessionSnapshot::SyncSessionSnapshot(
     const SyncerStatus& syncer_status,
     const ErrorCounters& errors,
     int64 num_server_changes_remaining,
-    int64 max_local_timestamp,
     bool is_share_usable,
     const syncable::ModelTypeBitSet& initial_sync_ended,
+    std::string download_progress_markers[syncable::MODEL_TYPE_COUNT],
     bool more_to_sync,
     bool is_silenced,
     int64 unsynced_count,
     int num_conflicting_updates,
     bool did_commit_items)
     : syncer_status(syncer_status),
       errors(errors),
       num_server_changes_remaining(num_server_changes_remaining),
-      max_local_timestamp(max_local_timestamp),
       is_share_usable(is_share_usable),
       initial_sync_ended(initial_sync_ended),
+      download_progress_markers(),
       has_more_to_sync(more_to_sync),
       is_silenced(is_silenced),
       unsynced_count(unsynced_count),
       num_conflicting_updates(num_conflicting_updates),
       did_commit_items(did_commit_items) {
+  for (int i = 0; i < syncable::MODEL_TYPE_COUNT; ++i) {
+    const_cast<std::string&>(this->download_progress_markers[i]).assign(
+        download_progress_markers[i]);
+  }
 }
 
 SyncSessionSnapshot::~SyncSessionSnapshot() {}
 
 ConflictProgress::ConflictProgress(bool* dirty_flag) : dirty_(dirty_flag) {}
 
 ConflictProgress::~ConflictProgress() {
   CleanupSets();
 }
 
@@ skipping 182 matching lines @@
 
 AllModelTypeState::~AllModelTypeState() {}
 
 PerModelSafeGroupState::PerModelSafeGroupState(bool* dirty_flag)
     : conflict_progress(dirty_flag) {
 }
 
 PerModelSafeGroupState::~PerModelSafeGroupState() {
 }
 
-PerModelTypeState::PerModelTypeState(bool* dirty_flag)
-    : current_download_timestamp(dirty_flag, 0) {
+PerModelTypeState::PerModelTypeState(bool* dirty_flag) {
 }
 
 PerModelTypeState::~PerModelTypeState() {
 }
 
 }  // namespace sessions
 }  // namespace browser_sync