path_content_summary fails on directories

[Jelmer Vernooij]

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464.156 opening working tree '/tmp/testbzr-xZBdDl.tmp'
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Text attachment: traceback
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Traceback (most recent call last):
File "/usr/lib/python2.7/dist-packages/testtools/runtest.py", line 169, in _run_user
return fn(*args, **kwargs)
File "/usr/lib/python2.7/dist-packages/testtools/testcase.py", line 508, in _run_test_method
return self._get_test_method()()
File "/home/jelmer/bzr-alltests/bzr.dev/bzrlib/tests/per_tree/test_path_content_summary.py", line 142, in test_dir_content_summary
summary = self._convert_tree(tree).path_content_summary('path')
File "/home/jelmer/bzr-alltests/bzr.dev/bzrlib/workingtree.py", line 846, in path_content_summary
if self._directory_is_tree_reference(path):
AttributeError: 'HgWorkingTree' object has no attribute '_directory_is_tree_reference'
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