Bug 987816  - Part 1/3. Allow verifying with certificateUsageVerifyCA. r=dkeeler

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extra : rebase_source : 7530839c9c02d56936e322f897de96d80a60a18f
Bug 987816 - Part 2/3. Test  verifying certificateUsageVerifyCA can return OK. r= dkeeler

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extra : rebase_source : 8e3f50d58c3c61e0fc843a053370f74d9adac8c0
Bug 987816 - Part 2/3. Update tests to match un-regressed behaviour. r=dkeeler

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extra : rebase_source : 7bccc66831f56cede353ec33275449b7bf2560b1