[Sync] Rename csync namespace to syncer

sync/engine/download_updates_command.h

Index: sync/engine/download_updates_command.h
diff --git a/sync/engine/download_updates_command.h b/sync/engine/download_updates_command.h
index 527844eb633886c5d3284a88e1f856d03be28671..56b73c8a9b30ccd6af5523207bc202a187d87ac8 100644
--- a/sync/engine/download_updates_command.h
+++ b/sync/engine/download_updates_command.h
@@ -18,7 +18,7 @@ namespace sync_pb {
 class EntitySpecifics;
 }
 
-namespace csync {
+namespace syncer {
 
 // Determine the enabled datatypes, download a batch of updates for them
 // from the server, place the result in the SyncSession for further processing.
@@ -59,7 +59,7 @@ class DownloadUpdatesCommand : public SyncerCommand {
   DISALLOW_COPY_AND_ASSIGN(DownloadUpdatesCommand);
 };
 
-}  // namespace csync
+}  // namespace syncer
 
 #endif  // SYNC_ENGINE_DOWNLOAD_UPDATES_COMMAND_H_