Adding some more escaping method.

      This will be used by the translate feature.

BUG=None
TEST=Run the unit-tests.

Review URL: http://codereview.chromium.org/548088

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@36715 0039d316-1c4b-4281-b951-d872f2087c98