[Sync] Rename csync namespace to syncer

sync/api/sync_error.h

Index: sync/api/sync_error.h
diff --git a/sync/api/sync_error.h b/sync/api/sync_error.h
index 6cd808aaaad3c29d8811388e6332c87e69d8a211..7e246763ab38e0bb09ab4ddf6e3d1158a5f4bbfc 100644
--- a/sync/api/sync_error.h
+++ b/sync/api/sync_error.h
@@ -16,7 +16,7 @@ namespace tracked_objects {
 class Location;
 }  // namespace tracked_objects
 
-namespace csync {
+namespace syncer {
 
 // Sync errors are used for debug purposes and handled internally and/or
 // exposed through Chrome's "about:sync" internal page. They are considered
@@ -84,6 +84,6 @@ class SyncError {
 // gmock printer helper.
 void PrintTo(const SyncError& sync_error, std::ostream* os);
 
-}  // namespace csync
+}  // namespace syncer
 
 #endif  // SYNC_API_SYNC_ERROR_H_