Buildbot Fix.
Buildbot Fix.

This method can be called with a '0' argument which checks the return
value. However, the method it calls doesn't expect '0' as a valid value. Call the
correct method when it's 0.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@164735 91177308-0d34-0410-b5e6-96231b3b80d8

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