Rename IS_CHROMEOS_ASH to IS_CHROMEOS in //components/dbus

Lacros is deprecated and IS_CHROMEOS_ASH is redundant now. We rename
everything to IS_CHROMEOS and remove lacros code.

Bug: 375523816, 373972275
Change-Id: I318cddf5a97f043ea44113caceefedd6fec0c3f6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6062898
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Hidehiko Abe <hidehiko@chromium.org>
Commit-Queue: Maksim Sisov <msisov@igalia.com>
Reviewed-by: Ryo Hashimoto <hashimoto@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1391492}

components/dbus/menu/BUILD.gn

@@ -38,7 +38,6 @@ source_set("unit_tests") {
     ":menu",
     "//base",
     "//build:chromecast_buildflags",
-    "//build:chromeos_buildflags",
     "//components/dbus/properties",
     "//testing/gtest",
   ]

components/dbus/menu/menu_property_list_unittest.cc

@@ -10,7 +10,6 @@
 #include "base/strings/utf_string_conversions.h"
 #include "build/build_config.h"
 #include "build/chromecast_buildflags.h"
-#include "build/chromeos_buildflags.h"
 #include "components/dbus/properties/types.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/base/accelerators/accelerator.h"

components/dbus/thread_linux/BUILD.gn

@@ -11,7 +11,6 @@ source_set("thread_linux") {
   defines = [ "IS_COMPONENTS_DBUS_IMPL" ]
   deps = [
     "//base",
-    "//build:chromeos_buildflags",
     "//dbus",
   ]
 }

components/dbus/thread_linux/dbus_thread_linux.h

@@ -9,14 +9,13 @@
 #include "base/memory/ref_counted.h"
 #include "base/task/single_thread_task_runner.h"
 #include "build/build_config.h"
-#include "build/chromeos_buildflags.h"
 
 // Many APIs in ::dbus are required to be called from the same thread
 // (https://crbug.com/130984). Therefore, a SingleThreadedTaskRunner is
 // maintained and accessible through GetTaskRunner(), from which all calls
 // to dbus on Linux have to be made.
 
-#if BUILDFLAG(IS_CHROMEOS_ASH)
+#if BUILDFLAG(IS_CHROMEOS)
 #error On ChromeOS, use DBusThreadManager instead.
 #endif