Add Media Router Mojo impl code.

chrome/browser/media/router/test_helper.cc

Index: chrome/browser/media/router/test_helper.cc
diff --git a/chrome/browser/media/router/test_helper.cc b/chrome/browser/media/router/test_helper.cc
new file mode 100644
index 0000000000000000000000000000000000000000..0657f1e938ec81b56a94a7ce12072759b382e123
--- /dev/null
+++ b/chrome/browser/media/router/test_helper.cc
@@ -0,0 +1,27 @@
+// 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 "chrome/browser/media/router/test_helper.h"
+
+namespace media_router {
+
+MockMediaSinksObserver::MockMediaSinksObserver(MediaRouter* router,
+                                               const MediaSource& source)
+    : MediaSinksObserver(router, source) {
+}
+MockMediaSinksObserver::~MockMediaSinksObserver() {
+}
+
+MockMediaRoutesObserver::MockMediaRoutesObserver(MediaRouter* router)
+    : MediaRoutesObserver(router) {
+}
+MockMediaRoutesObserver::~MockMediaRoutesObserver() {
+}
+
+MockEventPageTracker::MockEventPageTracker() {
+}
+MockEventPageTracker::~MockEventPageTracker() {
+}
+
+}  // namespace media_router