Turn test runner library into an actual component

components/test_runner/web_test_interfaces.cc

 // Copyright 2013 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/test_runner/web_test_interfaces.h"
 
 #include "components/test_runner/app_banner_client.h"
 #include "components/test_runner/mock_web_audio_device.h"
 #include "components/test_runner/mock_web_media_stream_center.h"
 #include "components/test_runner/mock_web_midi_accessor.h"
@@ skipping 68 matching lines @@
   return new MockWebAudioDevice(sample_rate);
 }
 
 scoped_ptr<blink::WebAppBannerClient>
 WebTestInterfaces::CreateAppBannerClient() {
   scoped_ptr<AppBannerClient> client(new AppBannerClient);
   interfaces_->SetAppBannerClient(client.get());
   return client.Pass();
 }
 
+AppBannerClient* WebTestInterfaces::GetAppBannerClient() {
+  return interfaces_->GetAppBannerClient();
+}
+
 }  // namespace test_runner