Cleanup //ui/shell_dialogs from LaCros support code.

No functional changes are done.

1) Removed chromeos_buildflags.h includes and deps
2) General clean ups (eg OWNERS file cleaned up from the lacros
ownership as there are no files left)

Bug: 373972275, 377324997
Change-Id: I18d02c6044b1a2aaafc2cd7554c964d7db1a110e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5993412


Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
Commit-Queue: Maksim Sisov <msisov@igalia.com>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1378922}

ui/shell_dialogs/BUILD.gn

@@ -2,7 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/config/chromeos/ui_mode.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//testing/test.gni")
@@ -34,7 +33,6 @@ component("shell_dialogs") {
   deps = [
     "//base",
     "//base:i18n",
-    "//build:chromeos_buildflags",
     "//skia",
     "//ui/base",
     "//ui/strings",

ui/shell_dialogs/DEPS

 include_rules = [
   "+chromeos/crosapi",
-  "+chromeos/lacros",
   "+components/dbus/thread_linux",
   "+components/dbus/utils",
   "+components/remote_cocoa",

ui/shell_dialogs/OWNERS

-per-file *lacros*=file://chromeos/LACROS_OWNERS
-
 per-file *linux*=thomasanderson@chromium.org
 
 per-file *win*=robliao@chromium.org

ui/shell_dialogs/shell_dialog_linux.cc

@@ -7,7 +7,6 @@
 #include "base/environment.h"
 #include "base/no_destructor.h"
 #include "base/notreached.h"
-#include "build/chromeos_buildflags.h"
 #include "ui/linux/linux_ui.h"
 #include "ui/shell_dialogs/select_file_dialog_linux.h"
 #include "ui/shell_dialogs/select_file_dialog_linux_kde.h"