libvpx: Pull from upstream

source/libvpx/build/make/gen_msvs_sln.sh

 #!/bin/bash
 ##
 ##  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.
 ##
@@ skipping 237 matching lines @@
     optval="${opt#*=}"
     case "$opt" in
     --help|-h) show_help
     ;;
     --out=*) outfile="${optval}"; mkoutfile="${optval}".mk
     ;;
     --dep=*) eval "${optval%%:*}_deps=\"\${${optval%%:*}_deps} ${optval##*:}\""
     ;;
     --ver=*) vs_ver="$optval"
              case $optval in
-             [789]|10|11)
+             [789]|10|11|12)
              ;;
              *) die Unrecognized Visual Studio Version in $opt
              ;;
              esac
     ;;
     --ver=*) vs_ver="$optval"
              case $optval in
              7) sln_vers="8.00"
                 sln_vers_str="Visual Studio .NET 2003"
              ;;
@@ skipping 21 matching lines @@
     ;;
     9) sln_vers="10.00"
        sln_vers_str="Visual Studio 2008"
     ;;
     10) sln_vers="11.00"
        sln_vers_str="Visual Studio 2010"
     ;;
     11) sln_vers="12.00"
        sln_vers_str="Visual Studio 2012"
     ;;
+    12) sln_vers="12.00"
+       sln_vers_str="Visual Studio 2013"
+    ;;
 esac
 case "${vs_ver:-8}" in
     [789])
     sfx=vcproj
     ;;
-    10|11)
+    10|11|12)
     sfx=vcxproj
     ;;
 esac
 
 for f in "${file_list[@]}"; do
     parse_project $f
 done
 cat  >${outfile} <<EOF
 Microsoft Visual Studio Solution File, Format Version $sln_vers${EOLDOS}
 # $sln_vers_str${EOLDOS}
 EOF
 for proj in ${proj_list}; do
     process_project $proj >>${outfile}
 done
 process_global >>${outfile}
 process_makefile >${mkoutfile}