[ObjC ARC] Converts ios/chrome/browser/ui/overscroll_actions:overscroll_actions to ARC.

ios/chrome/browser/ui/overscroll_actions/BUILD.gn

 # Copyright 2016 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.
 
 bundle_data("resources") {
   sources = [
     "resources/ptr_close.png",
     "resources/ptr_close@2x.png",
     "resources/ptr_close@3x.png",
     "resources/ptr_close_active.png",
@@ skipping 11 matching lines @@
     "resources/ptr_reload_active.png",
     "resources/ptr_reload_active@2x.png",
     "resources/ptr_reload_active@3x.png",
   ]
   outputs = [
     "{{bundle_resources_dir}}/{{source_file_part}}",
   ]
 }
 
 source_set("overscroll_actions") {
+  configs += [ "//build/config/compiler:enable_arc" ]
   sources = [
     "overscroll_actions_controller.h",
     "overscroll_actions_controller.mm",
     "overscroll_actions_gesture_recognizer.h",
     "overscroll_actions_gesture_recognizer.mm",
     "overscroll_actions_view.h",
     "overscroll_actions_view.mm",
   ]
   deps = [
     ":resources",
     "//base",
     "//ios/chrome/app/theme",
     "//ios/chrome/browser/ui",
     "//ios/chrome/browser/ui/static_content",
     "//ios/chrome/browser/ui/toolbar",
     "//ios/chrome/browser/ui/util",
     "//ios/chrome/browser/ui/voice",
     "//ios/web",
   ]
   allow_circular_includes_from = [ "//ios/chrome/browser/ui/static_content" ]
   libs = [
     "QuartzCore.framework",
     "UIKit.framework",
   ]
 }