Add a const version of a method, to be consistent with other methods of the same type.  I think this was just an oversight before.
Add a const version of a method, to be consistent with other methods
of the same type.  I think this was just an oversight before.

Reviewed by chandlerc.  Submitted as an "obvious" fix.


git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@107737 91177308-0d34-0410-b5e6-96231b3b80d8

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