Revert of Cleanup: Remove unneeded SSE2 checks and unused code.

media/base/simd/convert_yuv_to_rgb_mmx.asm

Index: media/base/simd/convert_yuv_to_rgb_mmx.asm
diff --git a/media/base/simd/convert_yuv_to_rgb_mmx.asm b/media/base/simd/convert_yuv_to_rgb_mmx.asm
new file mode 100644
index 0000000000000000000000000000000000000000..7395419d442ee6f74df6ce4d0c2ea9926f628a74
--- /dev/null
+++ b/media/base/simd/convert_yuv_to_rgb_mmx.asm
@@ -0,0 +1,23 @@
+; 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 "third_party/x86inc/x86inc.asm"
+
+;
+; This file uses MMX instructions.
+;
+  SECTION_TEXT
+  CPU       MMX
+
+; Use movq to save the output.
+%define MOVQ movq
+
+; extern "C" void ConvertYUVToRGB32Row_MMX(const uint8* y_buf,
+;                                          const uint8* u_buf,
+;                                          const uint8* v_buf,
+;                                          uint8* rgb_buf,
+;                                          ptrdiff_t width,
+;                                          const int16 convert_table[1024][4]);
+%define SYMBOL ConvertYUVToRGB32Row_MMX
+%include "convert_yuv_to_rgb_mmx.inc"