libvpx: Add VP9 decoder.

source/libvpx/vp9/common/vp9_mv.h

+/*
+ *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+
+#ifndef VP9_COMMON_VP9_MV_H_
+#define VP9_COMMON_VP9_MV_H_
+#include "vpx/vpx_integer.h"
+
+typedef struct {
+  short row;
+  short col;
+} MV;
+
+typedef union int_mv {
+  uint32_t as_int;
+  MV as_mv;
+} int_mv; /* facilitates faster equality tests and copies */
+
+#endif