Remove explicit singletonness of ArcBridgeService part 3.

chrome/browser/ui/app_list/arc/arc_app_list_prefs.cc

Index: chrome/browser/ui/app_list/arc/arc_app_list_prefs.cc
diff --git a/chrome/browser/ui/app_list/arc/arc_app_list_prefs.cc b/chrome/browser/ui/app_list/arc/arc_app_list_prefs.cc
index c64051c808ef98c0c64b046574872f9625663c70..c7c8218560a6618a85f2ccb7e9790778e84889a1 100644
--- a/chrome/browser/ui/app_list/arc/arc_app_list_prefs.cc
+++ b/chrome/browser/ui/app_list/arc/arc_app_list_prefs.cc
@@ -21,7 +21,7 @@
 #include "chrome/browser/ui/app_list/arc/arc_package_syncable_service.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/grit/generated_resources.h"
-#include "components/arc/arc_bridge_service.h"
+#include "components/arc/arc_service_manager.h"
 #include "components/crx_file/id_util.h"
 #include "components/pref_registry/pref_registry_syncable.h"
 #include "components/prefs/scoped_user_pref_update.h"
@@ -255,16 +255,12 @@ ArcAppListPrefs::ArcAppListPrefs(
 }
 
 ArcAppListPrefs::~ArcAppListPrefs() {
-  // A reference to ArcBridgeService is kept here so that it would crash the
-  // tests where ArcBridgeService and ArcAppListPrefs are not destroyed in right
-  // order.
-  arc::ArcBridgeService* bridge_service = arc::ArcBridgeService::Get();
-  if (bridge_service)
-    app_instance_holder_->RemoveObserver(this);
-
   arc::ArcSessionManager* arc_session_manager = arc::ArcSessionManager::Get();
-  if (arc_session_manager)
-    arc_session_manager->RemoveObserver(this);
+  if (!arc_session_manager)
+    return;
+  DCHECK(arc::ArcServiceManager::Get());
+  arc_session_manager->RemoveObserver(this);
+  app_instance_holder_->RemoveObserver(this);
 }
 
 void ArcAppListPrefs::StartPrefs() {