Bug 1066259 - Fix operators for multiplying/dividing a Coord by a Scale. r=kats

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extra : rebase_source : e6efebeac8b6628b24e1596fb5dc78187c64e325
Bug 1066259 - Change Axis to operate in Screen pixels where possible. r=kats

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extra : rebase_source : c31c5a16e46eb79c64fd6e6d42c1d84f4718c2fe