Add extra unit test to avoid off-by-one errors
Add extra unit test to avoid off-by-one errors

I was worried about this problem, and realized I didn't
have a unit test to ensure the correctness in this
case.  This just adds a unit test.

r=rvargas
Review URL: http://codereview.chromium.org/3535009

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@62354 0039d316-1c4b-4281-b951-d872f2087c98

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