libvpx: Pull from upstream

source/libvpx/args.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.
  */
 
@@ skipping 33 matching lines @@
 
 struct arg arg_init(char **argv);
 int arg_match(struct arg *arg_, const struct arg_def *def, char **argv);
 const char *arg_next(struct arg *arg);
 void arg_show_usage(FILE *fp, const struct arg_def *const *defs);
 char **argv_dup(int argc, const char **argv);
 
 unsigned int arg_parse_uint(const struct arg *arg);
 int arg_parse_int(const struct arg *arg);
 struct vpx_rational arg_parse_rational(const struct arg *arg);
+int arg_parse_enum(const struct arg *arg);
 int arg_parse_enum_or_int(const struct arg *arg);
 #ifdef __cplusplus
 }  // extern "C"
 #endif
 
 #endif  // ARGS_H_