Move //chromeos/{=>ash/components}/network [5/N]

This CL moves proxy/ to chromeos/ash/components/network and
migrates into a new target with the newly created BUILD.gn.

This CL is part of the Chrome OS source code directory migration:
https://docs.google.com/document/d/1g-98HpzA8XcoGBWUv1gQNr4rbnD5yfvbtYZyPDDbkaE.

Bug: 1164001
Change-Id: I6ea38eb25a4a05e212e0004156e009bd8170e981
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3653376
Reviewed-by: Steven Bennetts <[email protected]>
Reviewed-by: Hidehiko Abe <[email protected]>
Commit-Queue: Yeunjoo Choi <[email protected]>
Owners-Override: Hidehiko Abe <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1010104}
diff --git a/chrome/browser/prefs/browser_prefs.cc b/chrome/browser/prefs/browser_prefs.cc
index d7669c86..c59e71a9 100644
--- a/chrome/browser/prefs/browser_prefs.cc
+++ b/chrome/browser/prefs/browser_prefs.cc
@@ -393,6 +393,7 @@
 #include "chrome/browser/ui/webui/settings/chromeos/os_settings_ui.h"
 #include "chrome/browser/upgrade_detector/upgrade_detector_chromeos.h"
 #include "chrome/browser/web_applications/externally_installed_web_app_prefs.h"
+#include "chromeos/ash/components/network/proxy/proxy_config_handler.h"
 #include "chromeos/components/local_search_service/search_metrics_reporter.h"
 #include "chromeos/components/quick_answers/public/cpp/quick_answers_prefs.h"
 #include "chromeos/network/cellular_esim_profile_handler_impl.h"
@@ -400,7 +401,6 @@
 #include "chromeos/network/fast_transition_observer.h"
 #include "chromeos/network/managed_cellular_pref_handler.h"
 #include "chromeos/network/network_metadata_store.h"
-#include "chromeos/network/proxy/proxy_config_handler.h"
 #include "chromeos/services/assistant/public/cpp/assistant_prefs.h"
 #include "chromeos/services/bluetooth_config/bluetooth_power_controller_impl.h"
 #include "chromeos/services/bluetooth_config/device_name_manager_impl.h"