[Sync] Move //sync to //components/sync.

components/sync/core_impl/attachments/proto/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//third_party/protobuf/proto_library.gni")
 
 proto_library("proto") {
   # This should only get compiled into the sync component.
-  visibility = [ "//sync:sync_core" ]
+  visibility = [ "//components/sync:sync_core" ]
 
   sources = [
     "attachment_store.proto",
   ]
   cc_generator_options = "dllexport_decl=SYNC_EXPORT:"
-  cc_include = "sync/base/sync_export.h"
+  cc_include = "components/sync/base/sync_export.h"
 
   defines = [ "SYNC_IMPLEMENTATION" ]
 }