arc-bridge: Enable ARC with a command-line flag

components/arc/arc_bridge_service_unittest.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/arc/arc_bridge_service.h"
 
 #include "base/memory/ref_counted.h"
 #include "base/run_loop.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "components/arc/common/arc_host_messages.h"
@@ skipping 50 matching lines @@
 
       case ArcBridgeService::State::STOPPED:
         message_loop_.PostTask(FROM_HERE, message_loop_.QuitWhenIdleClosure());
         break;
 
       default:
         break;
     }
   }
 
-  void OnInstanceBootPhase(InstanceBootPhase boot_phase) {
+  void OnInstanceBootPhase(InstanceBootPhase boot_phase) override {
     boot_phase_ = boot_phase;
   }
 
   bool ready() const { return ready_; }
   InstanceBootPhase boot_phase() const { return boot_phase_; }
   ArcBridgeService::State state() const { return state_; }
 
  protected:
   scoped_ptr<IPCSenderFake> fake_sender_;
 
@@ skipping 103 matching lines @@
   ASSERT_TRUE(state() == ArcBridgeService::State::STOPPING ||
               state() == ArcBridgeService::State::STOPPED);
 
   base::RunLoop run_loop;
   run_loop.Run();
 
   ASSERT_EQ(ArcBridgeService::State::STOPPED, state());
 }
 
 }  // namespace arc