Remove unused MockMediaObserver

content/browser/renderer_host/media/mock_media_observer.cc

Index: content/browser/renderer_host/media/mock_media_observer.cc
diff --git a/content/browser/renderer_host/media/mock_media_observer.cc b/content/browser/renderer_host/media/mock_media_observer.cc
deleted file mode 100644
index 731801fe798c7efe477c5fa2bf76c7c977ba1393..0000000000000000000000000000000000000000
--- a/content/browser/renderer_host/media/mock_media_observer.cc
+++ /dev/null
@@ -1,13 +0,0 @@
-// Copyright (c) 2011 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 "content/browser/renderer_host/media/mock_media_observer.h"
-
-namespace content {
-
-MockMediaObserver::MockMediaObserver() {}
-
-MockMediaObserver::~MockMediaObserver() {}
-
-}  // namespace content