[Sync] Rename csync namespace to syncer

sync/util/nigori.cc

Index: sync/util/nigori.cc
diff --git a/sync/util/nigori.cc b/sync/util/nigori.cc
index f68956d9df6706cfe6f94e0830e13a9afe27c57d..f2ee83dffba3d0b9036957fc0e69e1f978d26a35 100644
--- a/sync/util/nigori.cc
+++ b/sync/util/nigori.cc
@@ -23,7 +23,7 @@ using crypto::Encryptor;
 using crypto::HMAC;
 using crypto::SymmetricKey;
 
-namespace csync {
+namespace syncer {
 
 // NigoriStream simplifies the concatenation operation of the Nigori protocol.
 class NigoriStream {
@@ -254,4 +254,4 @@ bool Nigori::ExportKeys(std::string* user_key,
       mac_key_->GetRawKey(mac_key);
 }
 
-}  // namespace csync
+}  // namespace syncer