APACHE_XLATE: in ap_send_error_response(), move the setting

APACHE_XLATE: in ap_send_error_response(), move the setting
of the translation handle to before we process ErrorDocument
strings.  The previous placement of this logic only handled
the hard-coded response documents.

When ErrorDocument specifies a redirection, we don't get here.
When the error response is headers only, we don't need to set
the handle for content.  Thus, all paths through
ap_send_error_response() should be handled now.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@85356 13f79535-47bb-0310-9956-ffa450edef68