path fillHits refactor

[guzba]

before:

rect Mask MaskBlend ................ 0.031 ms      0.035 ms    ±0.007  x1000
rect Mask SubtractMaskBlend ........ 0.225 ms      0.228 ms    ±0.007  x1000
rect Mask ExcludeMaskBlend ......... 0.215 ms      0.218 ms    ±0.007  x1000

after:

rect Mask MaskBlend ................ 0.009 ms      0.009 ms    ±0.001  x1000
rect Mask SubtractMaskBlend ........ 0.067 ms      0.068 ms    ±0.004  x1000
rect Mask ExcludeMaskBlend ......... 0.076 ms      0.076 ms    ±0.001  x1000