Bug 1038486 - Fix Linux desktop seccomp sandbox build on 32-bit x86. r=kang

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extra : amend_source : 130d2cbd485734997739ea96ac5d83c01899d8b0
Bug 1038490 - Fix misuse of MOZ_WIDGET_GONK in Linux content process sandbox policy. r=kang

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extra : amend_source : 0a7fe8ca751b59102cbc23316b18982268306423