Bug 1062249 - Vastly simplify the various GetCanvasTM methods. r=longsonr

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extra : rebase_source : b0ba980a34c720bd3c3f3c95733083e92f0c0513
Bug 1064087 - Remove nsRenderingContext::InvertRect(). r=Bas

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extra : rebase_source : 64ed4f9fa0e2e67aef00209dfc060dc9e87fc24a
Bug 1065127 - Avoid Matrix().Translate()/Scale()/Rotate() multiplication in lots of places. r=Bas

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extra : rebase_source : ef075258c31973c4943b9b3a9229685a9bb83917