Move display preference code from ash/display/ to ui/display/manager/.

ash/BUILD.gn

Index: ash/BUILD.gn
diff --git a/ash/BUILD.gn b/ash/BUILD.gn
index df0b83bceed61b0b60f9c7ace3ae4ff6eca290db..837a0d9405b11a814fe6b9004809fc48cc5c05ad 100644
--- a/ash/BUILD.gn
+++ b/ash/BUILD.gn
@@ -603,15 +603,12 @@ component("ash") {
     "display/display_configuration_controller.h",
     "display/display_error_observer_chromeos.cc",
     "display/display_error_observer_chromeos.h",
-    "display/display_pref_util.h",
     "display/display_util.cc",
     "display/display_util.h",
     "display/event_transformation_handler.cc",
     "display/event_transformation_handler.h",
     "display/extended_mouse_warp_controller.cc",
     "display/extended_mouse_warp_controller.h",
-    "display/json_converter.cc",
-    "display/json_converter.h",
     "display/mirror_window_controller.cc",
     "display/mirror_window_controller.h",
     "display/mouse_cursor_event_filter.cc",
@@ -1305,7 +1302,6 @@ test("ash_unittests") {
     "display/display_manager_unittest.cc",
     "display/display_util_unittest.cc",
     "display/extended_mouse_warp_controller_unittest.cc",
-    "display/json_converter_unittest.cc",
     "display/mirror_window_controller_unittest.cc",
     "display/mouse_cursor_event_filter_unittest.cc",
     "display/projecting_observer_chromeos_unittest.cc",