Remove most remaining sync/notifier dependencies

sync/notifier/invalidator.cc

Index: sync/notifier/invalidator.cc
diff --git a/sync/engine/update_handler.cc b/sync/notifier/invalidator.cc
similarity index 65%
copy from sync/engine/update_handler.cc
copy to sync/notifier/invalidator.cc
index 308fee95bb1074c197b6973f38b49eb017d9ba7c..5508b89a246556e4d32c185d18ea4d6665299c08 100644
--- a/sync/engine/update_handler.cc
+++ b/sync/notifier/invalidator.cc
@@ -2,13 +2,14 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "sync/engine/update_handler.h"
+#include "sync/notifier/invalidator.h"
 
 namespace syncer {
 
-UpdateHandler::UpdateHandler() {}
-
-UpdateHandler::~UpdateHandler() {}
+Invalidator::Invalidator() {
+}
 
+Invalidator::~Invalidator() {
+}
 
 }  // namespace syncer