Fix XPointer bug.

BUG=125462
AUTHOR=asd@ut.ee
R=cevans@chromium.org
Review URL: https://chromiumcodereview.appspot.com/10344022

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@135174 0039d316-1c4b-4281-b951-d872f2087c98