git: support rules

[Jelmer Vernooij]

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490.951 opening working tree '/tmp/testbzr-cghc3K.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_iter_search_rules.py", line 50, in test_iter_search_rules_no_tree
_default_searcher=per_user))
File "/home/jelmer/bzr-alltests/bzr.dev/bzrlib/tree.py", line 701, in iter_search_rules
searcher = self._get_rules_searcher(_default_searcher)
File "/home/jelmer/bzr-alltests/bzr.dev/bzrlib/workingtree.py", line 2687, in _get_rules_searcher
if self._rules_searcher is None:
AttributeError: 'GitWorkingTree' object has no attribute '_rules_searcher'

[Jelmer Vernooij (jelmer)]

This no longer throws an exception; for the work to support the equivalent of rules in Git repositories, see pad.lv/1802797