Update libxml gyp and BUILD.gn, was missing some .h files

third_party/libxml/libxml.gyp

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 {
   'variables': {
     'conditions': [
       # Define an "os_include" variable that points at the OS-specific generated
       # headers.  These were generated by running the configure script offline.
       ['os_posix == 1 and OS != "mac" and OS != "ios"', {
@@ skipping 113 matching lines @@
             'src/include/libxml/xmlschemas.h',
             'src/include/libxml/xmlschemastypes.h',
             'src/include/libxml/xmlstring.h',
             'src/include/libxml/xmlunicode.h',
             'src/include/libxml/xmlwriter.h',
             'src/include/libxml/xpath.h',
             'src/include/libxml/xpathInternals.h',
             'src/include/libxml/xpointer.h',
             'src/include/win32config.h',
             'src/include/wsockcompat.h',
-            'src/acconfig.h',
             'src/buf.c',
             'src/buf.h',
             'src/c14n.c',
             'src/catalog.c',
             'src/chvalid.c',
             'src/debugXML.c',
             'src/dict.c',
             'src/DOCBparser.c',
             'src/elfgcchack.h',
+            'src/enc.h',
             'src/encoding.c',
             'src/entities.c',
             'src/error.c',
             'src/globals.c',
             'src/hash.c',
             'src/HTMLparser.c',
             'src/HTMLtree.c',
             'src/legacy.c',
             'src/libxml.h',
             'src/list.c',
             'src/parser.c',
             'src/parserInternals.c',
             'src/pattern.c',
             'src/relaxng.c',
+            'src/save.h',
             'src/SAX.c',
             'src/SAX2.c',
             'src/schematron.c',
             'src/threads.c',
+            'src/timsort.h',
             'src/tree.c',
             #'src/trio.c',
             #'src/trio.h',
             #'src/triodef.h',
             #'src/trionan.c',
             #'src/trionan.h',
             #'src/triop.h',
             #'src/triostr.c',
             #'src/triostr.h',
             'src/uri.c',
             'src/valid.c',
             'src/xinclude.c',
             'src/xlink.c',
             'src/xmlIO.c',
             'src/xmlmemory.c',
             'src/xmlmodule.c',
             'src/xmlreader.c',
             'src/xmlregexp.c',
             'src/xmlsave.c',
             'src/xmlschemas.c',
             'src/xmlschemastypes.c',
             'src/xmlstring.c',
             'src/xmlunicode.c',
             'src/xmlwriter.c',
             'src/xpath.c',
             'src/xpointer.c',
+            #'src/xzlib.c',
+            'src/xzlib.h',
             'win32/config.h',
             'win32/include/libxml/xmlversion.h',
           ],
           'defines': [
             # Define LIBXML_STATIC as nothing to match how libxml.h
             # (an internal header) defines LIBXML_STATIC, otherwise
             # we get the macro redefined warning from GCC.  (-DFOO
             # defines the macro FOO as 1.)
             'LIBXML_STATIC=',
           ],
@@ skipping 60 matching lines @@
             }],
           ],
         }],
         ['OS == "ios"', {
           'toolsets': ['host', 'target'],
         }],
       ],
     },
   ],
 }