Bug 956081 - Fix the CC's GC-has-been-run detection in the presence of GGC; r=mccr8

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extra : rebase_source : de945b8e2f4972cb8b563f17a95c66cbba86a902
Bug 969410 - Do not expose non-tenured addresses in JS_GetObjectId; r=sfink

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extra : rebase_source : dfa32a19df80b9ae5f9d7d535b141e50007c0149