Auto merge of #401 - servo:revert, r=SimonSapin
Auto merge of #401 - servo:revert, r=SimonSapin

Revert "Remove unnecessary bounds checking in a couple places."

This reverts commit d3dfbf3123258fe27649dc74f0dd07a14a5801b2.

Let’s not add `unsafe` code gratuitously.

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servo/rust-url,servo/rust-url