libvpx: Pull from upstream

source/libvpx/y4menc.h

Index: source/libvpx/y4menc.h
===================================================================
--- source/libvpx/y4menc.h	(revision 0)
+++ source/libvpx/y4menc.h	(revision 0)
@@ -0,0 +1,33 @@
+/*
+ *  Copyright (c) 2014 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 Y4MENC_H_
+#define Y4MENC_H_
+
+#include "./tools_common.h"
+
+#include "vpx/vpx_decoder.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define Y4M_BUFFER_SIZE 128
+
+int y4m_write_file_header(char *buf, size_t len, int width, int height,
+                          const struct VpxRational *framerate,
+                          vpx_img_fmt_t fmt);
+int y4m_write_frame_header(char *buf, size_t len);
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
+#endif  // Y4MENC_H_