Bug 1010586 - IonMonkey: Shrink the MUse class by making the index field unnecessary. r=nbp
Bug 1010586 - IonMonkey: Eliminate the isObserved flag and compute observability on demand. r=nbp
Bug 1007027 - IonMonkey: Don't do backedge type processing for resume points in deleted blocks. r=nbp
Bug 1010586 - IonMonkey: Make MUse enforce use-list invariants automatically. r=nbp