Bug 958951 - Return IteratorResult object for completed generators instead of throwing. r=jorendorff

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extra : rebase_source : 8f9d5f592ac36713fe66a471c7213ac297d232cb
Bug 952870 - Treat -0 and 0 as the same key in Maps and Sets. r=jorendorff

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extra : rebase_source : c5fb6daf43530d67bfb60c24ac8ceecd2fa0b60d
Bug 960513 - Ensure LazyScript has script set for non-lazy canonical functions. r=jandem

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extra : rebase_source : ae490f18cd2a78c2d7afecf9ee32f11c38ab3cda