Description of problem: after changelog disable during geo-rep, if worker restarts it keeps crashing with "AttributeError: '_GMaster' object has no attribute 'changelog_register_time'". This happened when changelog was disable while creating and syncing hardlinks in geo-rep setup. But worked crashed with following traceback and this issue is being tracked with Bug 1098426
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[2014-07-23 16:34:09.840315] E [syncdutils(/bricks/brick3/master_b9):270:log_raise_exception] <top>: FAIL: 
Traceback (most recent call last):
  File "/usr/libexec/glusterfs/python/syncdaemon/gsyncd.py", line 164, in main
    main_i()
  File "/usr/libexec/glusterfs/python/syncdaemon/gsyncd.py", line 643, in main_i
    local.service_loop(*[r for r in [remote] if r])
  File "/usr/libexec/glusterfs/python/syncdaemon/resource.py", line 1323, in service_loop
    g1.crawlwrap()
  File "/usr/libexec/glusterfs/python/syncdaemon/master.py", line 502, in crawlwrap
    self.crawl()
  File "/usr/libexec/glusterfs/python/syncdaemon/master.py", line 1272, in crawl
    self.process([item[1]], 0)
  File "/usr/libexec/glusterfs/python/syncdaemon/master.py", line 899, in process
    self.process_change(change, done, retry)
  File "/usr/libexec/glusterfs/python/syncdaemon/master.py", line 863, in process_change
    self.slave.server.entry_ops(entries)
  File "/usr/libexec/glusterfs/python/syncdaemon/repce.py", line 226, in __call__
    return self.ins(self.meth, *a)
  File "/usr/libexec/glusterfs/python/syncdaemon/repce.py", line 208, in __call__
    raise res
OSError: [Errno 22] Invalid argument
[2014-07-23 16:34:09.846282] I [syncdutils(/bricks/brick3/master_b9):214:finalize] <top>: exiting.
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This caused restart of the worker, and then it got stuck by crashing with AttributeError everytime it restarts. 
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[2014-07-23 16:34:34.740226] E [syncdutils(/bricks/brick3/master_b9):270:log_raise_exception] <top>: FAIL: 
Traceback (most recent call last):
  File "/usr/libexec/glusterfs/python/syncdaemon/gsyncd.py", line 164, in main
    main_i()
  File "/usr/libexec/glusterfs/python/syncdaemon/gsyncd.py", line 643, in main_i
    local.service_loop(*[r for r in [remote] if r])
  File "/usr/libexec/glusterfs/python/syncdaemon/resource.py", line 1302, in service_loop
    g3.crawlwrap(oneshot=True)
  File "/usr/libexec/glusterfs/python/syncdaemon/master.py", line 502, in crawlwrap
    self.crawl()
  File "/usr/libexec/glusterfs/python/syncdaemon/master.py", line 1175, in crawl
    (purge_time[0], self.changelog_register_time))
AttributeError: '_GMaster' object has no attribute 'changelog_register_time'
[2014-07-23 16:34:34.747419] I [syncdutils(/bricks/brick3/master_b9):214:finalize] <top>: exiting.
===========================================================================


Version-Release number of selected component (if applicable): glusterfs-3.6.0.25-1.el6rhs


How reproducible: If conditions satisfy, it will happen everytime


Steps to Reproduce:
1. create and start a geo-rep relationship between master and slave. 
2. create data on master and let it sync on slave. 
3. then start creating hardlinks to created data and while creating hardlinks, disable changelog
4. If it doesn't hit with above steps, try to kill worker after changelog disable and before worker goes to hybrid crawl. 


Actual results: worker keeps crashing everytime it restarts 


Expected results: worker shouldn't crash. 


Additional info: