Code review comment for lp:~kbielefe/bzr/551391-log-memory-usage

This actually causes one correct test failure:

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FAIL: bzrlib.tests.test_trace.TestTrace.test_format_memory_error
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_StringException: Text attachment: log
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1966.897 Traceback (most recent call last):
 File "/home/pqm/bzr-pqm-workdir/home/+trunk/bzrlib/tests/test_trace.py", line 79, in test_format_memory_error
   raise MemoryError()
MemoryError

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Text attachment: traceback
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Traceback (most recent call last):
 File "/usr/lib/python2.4/site-packages/testtools/runtest.py", line 128, in _run_user
   return fn(*args)
 File "/usr/lib/python2.4/site-packages/testtools/testcase.py", line 368, in _run_test_method
   testMethod()
 File "/home/pqm/bzr-pqm-workdir/home/+trunk/bzrlib/tests/test_trace.py", line 84, in test_format_memory_error
   "bzr: out of memory\n")
AssertionError: not equal:
a = 'bzr: out of memory\nUse -Dmem_dump to dump memory to a file.\n'
b = 'bzr: out of memory\n'

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That's nice because we can check it is actually being printed.