Added a missing rethrow statement. The xml parser would

eat exceptions thrown by event handlers rather than letting
them propagate out as documented in the specification.

--HG--
extra : convert_revision : svn%3Afdd8eb12-d10e-0410-9acb-85c331704f74/trunk%403095

dlib/xml_parser/xml_parser_kernel_1.h

@@ -621,6 +621,8 @@ namespace dlib
             // restore the old exception settings to in
             in.exceptions(old_exceptions);
 
+            // don't forget to rethrow the exception
+            throw;
         }
 
         // restore the old exception settings to in