[Sync] Rename csync namespace to syncer

sync/engine/syncproto.h

Index: sync/engine/syncproto.h
diff --git a/sync/engine/syncproto.h b/sync/engine/syncproto.h
index ec6c6e4539eeb0a9417def46f2321bbcb5901ba8..8fa46976641e1c4e054b037353b971678e03c7a4 100644
--- a/sync/engine/syncproto.h
+++ b/sync/engine/syncproto.h
@@ -12,7 +12,7 @@
 #include "sync/protocol/sync.pb.h"
 #include "sync/syncable/syncable_id.h"
 
-namespace csync {
+namespace syncer {
 
 template<class Base>
 class IdWrapper : public Base {
@@ -82,6 +82,6 @@ typedef sync_pb::CommitResponse CommitResponse;
 typedef sync_pb::GetUpdatesResponse GetUpdatesResponse;
 typedef sync_pb::GetUpdatesMessage GetUpdatesMessage;
 
-}  // namespace csync
+}  // namespace syncer
 
 #endif  // SYNC_ENGINE_SYNCPROTO_H_