sync: use progress markers instead of timestamps during GetUpdates

chrome/browser/sync/profile_sync_service.cc

 // Copyright (c) 2010 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/profile_sync_service.h"
 
 #include <map>
 #include <set>
 
 #include "app/l10n_util.h"
@@ skipping 762 matching lines @@
         { SyncBackendHost::Status::OFFLINE_UNUSABLE };
     return status;
   }
 }
 
 bool ProfileSyncService::SetupInProgress() const {
   return !HasSyncSetupCompleted() && WizardIsVisible();
 }
 
 std::string ProfileSyncService::BuildSyncStatusSummaryText(
-  const sync_api::SyncManager::Status::Summary& summary) {
-  switch (summary) {
-    case sync_api::SyncManager::Status::OFFLINE:
-      return "OFFLINE";
-    case sync_api::SyncManager::Status::OFFLINE_UNSYNCED:
-      return "OFFLINE_UNSYNCED";
-    case sync_api::SyncManager::Status::SYNCING:
-      return "SYNCING";
-    case sync_api::SyncManager::Status::READY:
-      return "READY";
-    case sync_api::SyncManager::Status::CONFLICT:
-      return "CONFLICT";
-    case sync_api::SyncManager::Status::OFFLINE_UNUSABLE:
-      return "OFFLINE_UNUSABLE";
-    case sync_api::SyncManager::Status::INVALID:  // fall through
-    default:
-      return "UNKNOWN";
+    const sync_api::SyncManager::Status::Summary& summary) {
+  const char* strings[] = {"INVALID", "OFFLINE", "OFFLINE_UNSYNCED", "SYNCING",
+      "READY", "CONFLICT", "OFFLINE_UNUSABLE"};
+  COMPILE_ASSERT(arraysize(strings) ==
+                 sync_api::SyncManager::Status::SUMMARY_STATUS_COUNT,
+                 enum_indexed_array);
+  if (summary < 0 ||
+      summary >= sync_api::SyncManager::Status::SUMMARY_STATUS_COUNT) {
+    LOG(DFATAL) << "Illegal Summary Value: " << summary;
+    return "UNKNOWN";
   }
+  return strings[summary];
 }
 
 bool ProfileSyncService::unrecoverable_error_detected() const {
   return unrecoverable_error_detected_;
 }
 
 string16 ProfileSyncService::GetLastSyncedTimeString() const {
   if (last_synced_time_.is_null())
     return l10n_util::GetStringUTF16(IDS_SYNC_TIME_NEVER);
 
@@ skipping 405 matching lines @@
   // is initialized, all enabled data types are consistent with one
   // another, and no unrecoverable error has transpired.
   if (unrecoverable_error_detected_)
     return false;
 
   if (!data_type_manager_.get())
     return false;
 
   return data_type_manager_->state() == DataTypeManager::CONFIGURED;
 }