Change //ash/components/account_manager namespace

Code in //ash should is the ash namespace. This CL is a follow-up from
https://crrev.com/c/2643727, which moved this component from
//chromeos/components.

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

Bug: 1164001
Change-Id: I26f7f795fff9aad07b8de61f9543438ddfe6271e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2643332
Commit-Queue: Henrique Ferreiro <[email protected]>
Owners-Override: James Cook <[email protected]>
Reviewed-by: James Cook <[email protected]>
Cr-Commit-Position: refs/heads/master@{#848461}
diff --git a/chrome/browser/prefs/browser_prefs.cc b/chrome/browser/prefs/browser_prefs.cc
index 20cf1bc..45b39cb 100644
--- a/chrome/browser/prefs/browser_prefs.cc
+++ b/chrome/browser/prefs/browser_prefs.cc
@@ -1010,7 +1010,7 @@
   arc::prefs::RegisterProfilePrefs(registry);
   ArcAppListPrefs::RegisterProfilePrefs(registry);
   certificate_manager::CertificatesHandler::RegisterProfilePrefs(registry);
-  chromeos::AccountManager::RegisterPrefs(registry);
+  ash::AccountManager::RegisterPrefs(registry);
   chromeos::ApkWebAppService::RegisterProfilePrefs(registry);
   chromeos::app_time::AppActivityRegistry::RegisterProfilePrefs(registry);
   chromeos::app_time::AppTimeController::RegisterProfilePrefs(registry);