Bug 1093573 part 12 - Inline INITIALYIELD and YIELD in Baseline. r=wingo

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extra : rebase_source : 9efa54ab41b250ad659443bd5409c179af478c68
Bug 1093573 part 13 - Handle closing legacy generators correctly. r=wingo,shu

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extra : rebase_source : d561bc9b8893e8cdff0941530a00824e47d097fc
Bug 1093573 part 14 - Remove newborn generator state. r=wingo

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extra : rebase_source : 63c0f3d2708867c891ed5c70aa9566d282eeabcf