Fix unused variable from r240792.
Fix unused variable from r240792.

The variable 'I' wasn't used when assertions were disabled.
This commit ensures that 'I' is used outside of an assert.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@240797 91177308-0d34-0410-b5e6-96231b3b80d8

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