[Sync] Rename csync namespace to syncer

sync/api/syncable_service.h

Index: sync/api/syncable_service.h
diff --git a/sync/api/syncable_service.h b/sync/api/syncable_service.h
index 5c828de6838ec8b803d482a388932c122de1fdb4..53e2cd532f9ad819fd1f436dec198b48d6a475de 100644
--- a/sync/api/syncable_service.h
+++ b/sync/api/syncable_service.h
@@ -16,7 +16,7 @@
 #include "sync/api/sync_error.h"
 #include "sync/internal_api/public/syncable/model_type.h"
 
-namespace csync {
+namespace syncer {
 
 class SyncErrorFactory;
 
@@ -64,6 +64,6 @@ class SyncableService : public SyncChangeProcessor,
   virtual ~SyncableService();
 };
 
-}  // namespace csync
+}  // namespace syncer
 
 #endif  // SYNC_API_SYNCABLE_SERVICE_H_