Bug 941095 - Part 1: Support SetPermitSubpixelAA with Quartz. r=bas

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extra : rebase_source : 69171a8a17a34c822b34f48babecf18ffa08bf56
Bug 941095 - Part 2: Disable subpixelaa + component alpha. r=mattwoodrow

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extra : rebase_source : 7e3a0d3710fb29b47615cc0254135d3b44637ed8