Revert r95841 due to failing media_unittests on linux_shared bot.

media/base/media_export.h

Index: media/base/media_export.h
===================================================================
--- media/base/media_export.h	(revision 95843)
+++ media/base/media_export.h	(working copy)
@@ -1,29 +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.
-
-#ifndef MEDIA_BASE_MEDIA_EXPORT_H_
-#define MEDIA_BASE_MEDIA_EXPORT_H_
-#pragma once
-
-// Defines MEDIA_EXPORT so that functionality implemented by the Media module
-// can be exported to consumers.
-
-#if defined(COMPONENT_BUILD)
-#if defined(WIN32)
-
-#if defined(MEDIA_IMPLEMENTATION)
-#define MEDIA_EXPORT __declspec(dllexport)
-#else
-#define MEDIA_EXPORT __declspec(dllimport)
-#endif  // defined(MEDIA_IMPLEMENTATION)
-
-#else  // defined(WIN32)
-#define MEDIA_EXPORT __attribute__((visibility("default")))
-#endif
-
-#else  // defined(COMPONENT_BUILD)
-#define MEDIA_EXPORT
-#endif
-
-#endif  // MEDIA_BASE_MEDIA_EXPORT_H_