Restore checked strlen conversions.
Restore checked strlen conversions.

The checked conversion can be re-enabled now that there is a public
API free of private headers like this one.

This reverts commit 6661fd4c26106cd530d187b36f29be7e5c98b70f.

R=thestig@chromium.org

Review URL: https://codereview.chromium.org/1133323003

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