[thrift] Error checking for T_OBJECT serialization

Summary: Avoid segfaulting via calling zend_fetch_class_entry on something
  that might not actually be an object; throw an exception instead.
Reviewed by: shire


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@665581 13f79535-47bb-0310-9956-ffa450edef68
1 file changed