Add ArcEnabled policy implementation

components/arc/arc_service_manager.cc

Index: components/arc/arc_service_manager.cc
diff --git a/components/arc/arc_service_manager.cc b/components/arc/arc_service_manager.cc
index d649cf30cff8376072d06ca49f0717acd06fb3ec..f3e07a8bd936772a0ce1ce0f891c01c8b02dc231 100644
--- a/components/arc/arc_service_manager.cc
+++ b/components/arc/arc_service_manager.cc
@@ -23,14 +23,23 @@ namespace {
 // Weak pointer.  This class is owned by ChromeBrowserMainPartsChromeos.
 ArcServiceManager* g_arc_service_manager = nullptr;
 
+// This pointer is owned by ArcServiceManager.
+ArcBridgeService* g_arc_bridge_service_for_testing = nullptr;
+
 }  // namespace
 
-ArcServiceManager::ArcServiceManager()
-    : arc_bridge_service_(
-          new ArcBridgeServiceImpl(ArcBridgeBootstrap::Create())) {
+ArcServiceManager::ArcServiceManager() {
   DCHECK(!g_arc_service_manager);
   g_arc_service_manager = this;
 
+  if (g_arc_bridge_service_for_testing) {
+    arc_bridge_service_.reset(g_arc_bridge_service_for_testing);
+    g_arc_bridge_service_for_testing = nullptr;
+  } else {
+    arc_bridge_service_.reset(new ArcBridgeServiceImpl(
+        ArcBridgeBootstrap::Create()));
+  }
+
   AddService(make_scoped_ptr(new ArcClipboardBridge(arc_bridge_service())));
   AddService(
       make_scoped_ptr(new ArcCrashCollectorBridge(arc_bridge_service())));
@@ -44,6 +53,9 @@ ArcServiceManager::~ArcServiceManager() {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(g_arc_service_manager == this);
   g_arc_service_manager = nullptr;
+  if (g_arc_bridge_service_for_testing) {
+    delete g_arc_bridge_service_for_testing;
+  }
 }
 
 // static
@@ -72,4 +84,13 @@ void ArcServiceManager::OnPrimaryUserProfilePrepared(
       new ArcNotificationManager(arc_bridge_service(), account_id)));
 }
 
+//static
+void ArcServiceManager::SetArcBridgeServiceForTesting(
+    scoped_ptr<ArcBridgeService> arc_bridge_service) {
+  if (g_arc_bridge_service_for_testing) {
+    delete g_arc_bridge_service_for_testing;
+  }
+  g_arc_bridge_service_for_testing = arc_bridge_service.release();
+}
+
 }  // namespace arc