Fix crash with unexpected DTD nodes in XSLT.

third_party/libxslt/README.chromium

 Name: libxslt
 URL: http://xmlsoft.org/XSLT
 Version: 1.1.26
 Security Critical: yes
 
 Description:
 This directory contains a partial snapshot of the libxslt library
 with the following modification:
 
 1) Modified win32/configure.js to be able to clobber a read-only Makefile
@@ skipping 22 matching lines @@
 
 4) Modified xsltconfig.h options:
 - Change LIBXSLT_VERSION_EXTRA define to ""
 - Change the DEBUG_MEMORY define to #if 0
 - Change the WITH_MODULES define to #if 0
 - Change the "Locale support" section to #if 0
 - For good measure, change the LIBXSLT_DEFAULT_PLUGINS_PATH() define to "NULL"
 
 Current version: 1.1.26, plus the following patches:
 - A fix to get more compact generated IDs (http://git.gnome.org/browse/libxslt/commit/?id=ecb6bcb8d1b7e44842edde3929f412d46b40c89f)
-- Import pattern parsing fix for commit: http://git.gnome.org/browse/libxslt/commit/?id=fe5a4fa33eb85bce3253ed3742b1ea6c4b59b41b 
+- Import pattern parsing fix for commit: http://git.gnome.org/browse/libxslt/commit/?id=fe5a4fa33eb85bce3253ed3742b1ea6c4b59b41b
+- A fix for XSLT node checking (from upstream, commit pending).
 
 
 To import a new snapshot of libxslt:
 
 - Visit http://xmlsoft.org/XSLT/downloads.html and download the latest source
   distribution.
 - Copy the files into this directory, omitting files which have been omitted
   here.
 - Run build/generate-win32-headers.bat to re-generate the configuration
   headers.
 - On Linux, 'cd linux && sh ../configure --with-libxml-src=../../libxml/linux/'
   to re-generate configuration headers.
 - On Mac, 'cd mac && sh ../configure --with-libxml-src=../../libxml/mac/'
   to re-generate configuration headers.
 - Perform the modification above.
 - Update this README to reflect the new version number.
 - When creating your CL, make sure to "svn add" any new source files, but
 don't ever add in the files not needed for the Chromium build. (e.g.
 Changelog, configure, etc) -- these are just bloat.