Cleanup ContentSuggestions cells

ios/chrome/browser/ui/content_suggestions/identifier/BUILD.gn

 # Copyright 2017 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.
 
 source_set("identifier") {
-  configs += [ "//build/config/compiler:enable_arc" ]
   sources = [
     "content_suggestion_identifier.h",
     "content_suggestion_identifier.mm",
     "content_suggestions_section_information.h",
     "content_suggestions_section_information.mm",
   ]
   deps = [
     "//base",
   ]
+  configs += [ "//build/config/compiler:enable_arc" ]
 }
 
 source_set("unit_tests") {
-  configs += [ "//build/config/compiler:enable_arc" ]
   testonly = true
   sources = [
     "content_suggestion_identifier_unittest.mm",
   ]
   deps = [
     ":identifier",
     "//testing/gtest",
   ]
+  configs += [ "//build/config/compiler:enable_arc" ]
 }