Bug 911142 - Make the "length" property of function objects configurable. r=Waldo.

Thanks to Till Schneidereit for a bunch of test fixes.

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extra : rebase_source : 85445692ad250df76d5c78a9b36b6e7dd691173f
Bug 1089609 - Fix findReferences-01.js regressed by recent changes to storage of getters and setters. r=jandem.

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extra : rebase_source : a6019afb7c1ec098eb9e9ac3394cd01ec41119d3
Bug 1080821 - Fix assertion when js_DumpPC is called from an empty stack. r=terrence.

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extra : rebase_source : 424867dc4d288affed4cef46b4a1966906bc668e