qlog: 'view file' does not work

[IWATA Hidetaka]

In trunk(r1148)
When executing 'view file' from context menu of qlog bottom-right pane, it reports following traceback.

bzr: ERROR: exceptions.AttributeError: 'RevisionTree' object has no attribute 'branch'

Traceback (most recent call last):
  File "C:/Program Files/Bazaar/plugins\qbzr\lib\util.py", line 878, in decorate
  File "C:/Program Files/Bazaar/plugins\qbzr\lib\util.py", line 890, in run_in_loading_queue
  File "C:/Program Files/Bazaar/plugins\qbzr\lib\uifactory.py", line 32, in decorate
  File "C:/Program Files/Bazaar/plugins\qbzr\lib\log.py", line 611, in show_file_content
  File "C:/Program Files/Bazaar/plugins\qbzr\lib\cat.py", line 74, in __init__
AttributeError: 'RevisionTree' object has no attribute 'branch'

bzr 2.0.2 on python 2.5.4 (win32)
arguments: ['bzr', 'qlog']
encoding: 'cp932', fsenc: 'mbcs', lang: 'en'
plugins:
  bzrtools C:\Program Files\Bazaar\plugins\bzrtools [2.0.1]
  explorer C:\Program Files\Bazaar\plugins\explorer [0.9.0]
  launchpad C:\Program Files\Bazaar\plugins\launchpad [2.0.2]
  netrc_credential_store C:\Program Files\Bazaar\plugins\netrc_credential_store [2.0.2]
  qbzr C:\Program Files\Bazaar\plugins\qbzr [0.17.0dev]
  rebase C:\Program Files\Bazaar\plugins\rebase [0.5.4]
  svn C:\Program Files\Bazaar\plugins\svn [1.0.0]
  upload C:\Program Files\Bazaar\plugins\upload [1.0.0dev]
  xmloutput C:\Program Files\Bazaar\plugins\xmloutput [0.8.5]

[Alexander Belchenko (bialix)]

I've just fixed this problem in revno 1151. Please, test.