Bug 1075059 - Part 1: Backout of Array.prototpype.contains usages. r=me

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extra : rebase_source : c40bca2849fdfee824560253c7ffe8fb93f9b774
Bug 1075059 - Part 2: Backout of Array.prototpype.contains. r=jorendorff

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extra : rebase_source : 088d2cc999b55eb2c6c0d43b47bc5f3cc6d9d69a