'test_second_level': expected item missing in set

[tseaver]

From: https://travis-ci.org/GoogleCloudPlatform/google-cloud-python/builds/158529136#L1386-L1393

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FAIL: test_second_level (storage.TestStoragePseudoHierarchy)
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Traceback (most recent call last):
  File "/home/travis/build/GoogleCloudPlatform/google-cloud-python/system_tests/storage.py", line 329, in test_second_level
    set(['parent/child/grand/', 'parent/child/other/']))
AssertionError: Items in the second set but not the first:
'parent/child/other/'

[dhermes]

Indeed. I've been tracking this on the last 5 or so builds. storage seems to be under duress (or just has different performance characteristics than before)

[dhermes]

I went at this in #2252, maybe the issue is with how the Iterator stores prefixes?

[dhermes]

I'm going to close this. I'm fairly certain that it was caused by #2289. We can re-open if we see the issue come back.