Delete media/base/yuv_convert and dependents. Prefer libyuv.

media/base/simd/media_export.asm

-; 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.
-;
-; A set of helper macros for controlling symbol visibility.
-;
-
-%ifndef MEDIA_BASE_SIMD_MEDIA_EXPORT_ASM_
-%define MEDIA_BASE_SIMD_MEDIA_EXPORT_ASM_
-
-; Necessary for the mangle() macro.
-%include "third_party/x86inc/x86inc.asm"
-
-;
-; PRIVATE
-; A flag representing the specified symbol is a private symbol. This define adds
-; a hidden flag on Linux and a private_extern flag on Mac. (We can use this
-; private_extern flag only on the latest yasm.)
-;
-%ifdef MACHO
-%define PRIVATE :private_extern
-%elifdef ELF
-%define PRIVATE :hidden
-%else
-%define PRIVATE
-%endif
-
-;
-; EXPORT %1
-; Designates a symbol as PRIVATE if EXPORT_SYMBOLS is not set.
-;
-%macro EXPORT 1
-%ifdef EXPORT_SYMBOLS
-global mangle(%1)
-
-; Windows needs an additional export declaration.
-%ifidn __OUTPUT_FORMAT__,win32
-export mangle(%1)
-%elifidn __OUTPUT_FORMAT__,win64
-export mangle(%1)
-%endif
-
-%else
-global mangle(%1) PRIVATE
-%endif
-%endmacro
-
-%endif  ; MEDIA_BASE_SIMD_MEDIA_EXPORT_ASM_