Bug 1011268 - Unregister algorithm. r=ehsan

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extra : rebase_source : 134f7db35f039891775cf45a6bfd2146e03b8e75
Bug 1057136 - ServiceWorkers use longest-match for scopes. r=ehsan,bz

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extra : rebase_source : e037a3c0f7d0923a5b6f5a06afe9f22abb91d5de