[Sync] Rename csync namespace to syncer

sync/engine/throttled_data_type_tracker.h

Index: sync/engine/throttled_data_type_tracker.h
diff --git a/sync/engine/throttled_data_type_tracker.h b/sync/engine/throttled_data_type_tracker.h
index f24ab74b7993535aade2090d506e135d9a0cff20..a496bea608facf31cd58bcace65105b1e04c3b69 100644
--- a/sync/engine/throttled_data_type_tracker.h
+++ b/sync/engine/throttled_data_type_tracker.h
@@ -11,7 +11,7 @@
 #include "base/gtest_prod_util.h"
 #include "sync/internal_api/public/syncable/model_type.h"
 
-namespace csync {
+namespace syncer {
 
 class AllStatus;
 
@@ -50,6 +50,6 @@ class ThrottledDataTypeTracker {
   DISALLOW_COPY_AND_ASSIGN(ThrottledDataTypeTracker);
 };
 
-}  // namespace csync
+}  // namespace syncer
 
 #endif  // SYNC_ENGINE_THROTTLED_DATA_TYPE_TRACKER_H_