Roll libxml to 2.9.3

third_party/libxml/src/m4/ltsugar.m4

 # ltsugar.m4 -- libtool m4 base layer.                         -*-Autoconf-*-
 #
-# Copyright (C) 2004, 2005, 2007, 2008 Free Software Foundation, Inc.
+# Copyright (C) 2004-2005, 2007-2008, 2011-2015 Free Software
+# Foundation, Inc.
 # Written by Gary V. Vaughan, 2004
 #
 # This file is free software; the Free Software Foundation gives
 # unlimited permission to copy and/or distribute it, with or without
 # modifications, as long as this notice is preserved.
 
 # serial 6 ltsugar.m4
 
 # This is to help aclocal find these macros, as it can't see m4_define.
 AC_DEFUN([LTSUGAR_VERSION], [m4_if([0.1])])
@@ skipping 12 matching lines @@
 m4_define([_lt_join],
 [m4_if([$#$2], [2], [],
        [m4_if([$2], [], [], [[$1$2]])$0([$1], m4_shift(m4_shift($@)))])])
 
 
 # lt_car(LIST)
 # lt_cdr(LIST)
 # ------------
 # Manipulate m4 lists.
 # These macros are necessary as long as will still need to support
-# Autoconf-2.59 which quotes differently.
+# Autoconf-2.59, which quotes differently.
 m4_define([lt_car], [[$1]])
 m4_define([lt_cdr],
 [m4_if([$#], 0, [m4_fatal([$0: cannot be called without arguments])],
        [$#], 1, [],
        [m4_dquote(m4_shift($@))])])
 m4_define([lt_unquote], $1)
 
 
 # lt_append(MACRO-NAME, STRING, [SEPARATOR])
 # ------------------------------------------
-# Redefine MACRO-NAME to hold its former content plus `SEPARATOR'`STRING'.
+# Redefine MACRO-NAME to hold its former content plus 'SEPARATOR''STRING'.
 # Note that neither SEPARATOR nor STRING are expanded; they are appended
 # to MACRO-NAME as is (leaving the expansion for when MACRO-NAME is invoked).
 # No SEPARATOR is output if MACRO-NAME was previously undefined (different
 # than defined and empty).
 #
 # This macro is needed until we can rely on Autoconf 2.62, since earlier
 # versions of m4sugar mistakenly expanded SEPARATOR but not STRING.
 m4_define([lt_append],
 [m4_define([$1],
            m4_ifdef([$1], [m4_defn([$1])[$3]])[$2])])
@@ skipping 56 matching lines @@
 
 
 # lt_dict_filter(DICT, [SUBKEY], VALUE, [SEPARATOR], KEY, [...])
 # --------------------------------------------------------------
 m4_define([lt_dict_filter],
 [m4_if([$5], [], [],
   [lt_join(m4_quote(m4_default([$4], [[, ]])),
            lt_unquote(m4_split(m4_normalize(m4_foreach(_Lt_key, lt_car([m4_shiftn(4, $@)]),
                       [lt_if_dict_fetch([$1], _Lt_key, [$2], [$3], [_Lt_key ])])))))])[]dnl
 ])