OPENDJ-1169 (CR-2438) Exception/error lost when logging ERR_LOOP_REPLAYING_OPERATION


LDAPReplicationDomain.replay() may lose error messages after too many replay attempts if "op" gets overwritten.


LDAPReplicationDomain.java:
In replay():
- Added the "nextOp" local variable so the code can keep error messages in the "op" local variable until the next loop iteration starts.
- Reduced as much as possible the scope of local variables to avoid the need to reinitialize them.
- Renamed "newOp" local variables to "castOp"