Bug 879616 - adjust close icons for OS X to deal with bright lightweight themes, r=MattN, a=sylvestre

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[Australis] Bug 983655: fix combined and menu-button buttons styling in the overflow panel. r=Gijs, a=sylvestre

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Bug 984188 - Don't invert icons for -moz-lwtheme-brighttext in the overflow panel. r=mikedeboer, a=sylvestre
[Australis]

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