[Clean Skeleton] Migrate code to clean/

ios/chrome/browser/BUILD.gn

 # Copyright 2015 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("//build/buildflag_header.gni")
 import("//build/config/features.gni")
 import("//build/config/ios/rules.gni")
 import("//rlz/features/features.gni")
 import("//third_party/protobuf/proto_library.gni")
 
@@ skipping 238 matching lines @@
 
 source_set("browser_internal") {
   sources = [
     "callback_counter.h",
     "callback_counter.mm",
   ]
   deps = [
     "//base",
   ]
 }
-
-# Clean Skeleton targets
-source_set("browser_clean_skeleton") {
-  sources = [
-    "browser_coordinator+internal.h",
-    "browser_coordinator.h",
-    "browser_coordinator.mm",
-    "url_opening.h",
-  ]
-
-  configs += [ "//build/config/compiler:enable_arc" ]
-
-  deps = [
-    ":browser",
-    "//base",
-    "//ios/chrome/browser/browser_state",
-  ]
-}