Bug 1081260 - Do not leak onOutOfMemory's allocation; r=luke

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extra : rebase_source : f37bd362ecb450ef479323d74b84cb8101e3faf9
Bug 1082794 - Use Maybe instead of a separate constructor to maybe construct an AutoLockGC; r=jonco

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extra : rebase_source : 7a4c24509fd6ac4b6f1bea403fd04638536d90d6