Revert "Add optimization of Skia S32A_Blend blitter"

This reverts commit 0b0a1a331a66b9d87c3b5522a17299816189155e.
Revert "Add optimization of Skia S32A_Opaque blitter"

This reverts commit accc1d91c89b7e007613ee12c1ba65708035dae1.