Merge "Rename SkSourceGammaTreatment to SkDestinationSurfaceColorMode" into master-skia

https://skia.googlesource.com/skia/+/7b8400dad2f82dcc6ed3c7cc1707ebaf85f04840

Change-Id: Ie141bd054f8a1f133b8832a9541c88d0553e0069