views: add layout delegates

ui/views/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("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//testing/test.gni")
 import("//ui/ozone/ozone.gni")
 
 config("flags") {
@@ skipping 259 matching lines @@
     "focus/view_storage.h",
     "focus/widget_focus_manager.cc",
     "focus/widget_focus_manager.h",
     "layout/box_layout.cc",
     "layout/box_layout.h",
     "layout/fill_layout.cc",
     "layout/fill_layout.h",
     "layout/grid_layout.cc",
     "layout/grid_layout.h",
     "layout/layout_constants.h",
+    "layout/layout_delegate.cc",
+    "layout/layout_delegate.h",
     "layout/layout_manager.cc",
     "layout/layout_manager.h",
     "linux_ui/linux_ui.cc",
     "linux_ui/linux_ui.h",
     "linux_ui/status_icon_linux.cc",
     "linux_ui/status_icon_linux.h",
     "linux_ui/window_button_order_observer.h",
     "linux_ui/window_button_order_provider.cc",
     "masked_targeter_delegate.cc",
     "masked_targeter_delegate.h",
@@ skipping 729 matching lines @@
       "//ui/base:test_support",
       "//ui/compositor",
       "//ui/events:test_support",
       "//ui/gl:test_support",
       "//ui/resources",
       "//ui/resources:ui_test_pak",
       "//ui/strings",
     ]
   }
 }