[arc] Don't bring up ScopedIPCSupport for unit tests

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 <utility>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/macros.h"
 #include "base/run_loop.h"
@@ skipping 66 matching lines @@
   scoped_ptr<ArcBridgeServiceImpl> service_;
   scoped_ptr<FakeArcBridgeInstance> instance_;
 
  private:
   void SetUp() override {
     chromeos::DBusThreadManager::Initialize();
 
     ready_ = false;
     state_ = ArcBridgeService::State::STOPPED;
 
-    ipc_support_.reset(new IPC::ScopedIPCSupport(message_loop_.task_runner()));
     instance_.reset(new FakeArcBridgeInstance());
     service_.reset(new ArcBridgeServiceImpl(
         make_scoped_ptr(new FakeArcBridgeBootstrap(instance_.get()))));
 
     service_->AddObserver(this);
   }
 
   void TearDown() override {
     service_->RemoveObserver(this);
     instance_.reset();
     service_.reset();
-    ipc_support_.reset();
 
     chromeos::DBusThreadManager::Shutdown();
   }
 
   bool ready_;
   ArcBridgeService::State state_;
-  scoped_ptr<IPC::ScopedIPCSupport> ipc_support_;
   base::MessageLoopForUI message_loop_;
 
   DISALLOW_COPY_AND_ASSIGN(ArcBridgeTest);
 };
 
 // Exercises the basic functionality of the ARC Bridge Service.  A message from
 // within the instance should cause the observer to be notified.
 TEST_F(ArcBridgeTest, Basic) {
   ASSERT_FALSE(ready());
   ASSERT_EQ(ArcBridgeService::State::STOPPED, state());
@@ skipping 47 matching lines @@
   service_->OnChannelClosed();
   instance_->WaitForInitCall();
   ASSERT_EQ(ArcBridgeService::State::READY, state());
   ASSERT_EQ(2, instance_->init_calls());
 
   service_->Shutdown();
   ASSERT_EQ(ArcBridgeService::State::STOPPED, state());
 }
 
 }  // namespace arc