Bug 1034627 part 4 - Fix XPCComponents and XPCWrappedJSClass to work with Latin1 strings and nursery strings. r=bholley

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extra : rebase_source : 82d0a3ab83d9f10391da38c5c658627d1701f07a
Bug 1034627 part 6 - Fix XPCVariant to work with Latin1 strings and nursery strings. r=bholley

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extra : rebase_source : be029c174195192570da688250583157825e9e06