Separate user and raw stencil settings

Separate user and raw stencil settings

Adds a new GrUserStencilSettings class that describes in abstract terms
how a draw will use the stencil (e.g. kAlwaysIfInClip, kSetClipBit,
etc.). GrPipelineBuilder now only defines the GrUserStencilSettings.
When the GrPipeline is finalized, the user stencil settings are then
translated into concrete GrStencilSettings.

At this point, GrClipMaskManager only needs to tell the GrAppliedClip
whether or not there is a stencil clip. It does not need to modify
stencil settings and GrPipelineBuilder does not need
AutoRestoreStencil.

This is one step of the stencil overhaul. In the future it will also
allow us to clean up the special case handling for nvpr and the
stateful fClipMode member of GrClipMaskManager.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1962243002

Committed: https://skia.googlesource.com/skia/+/12dbb3947e1aaf205b4fcf13b40e54e50650eb37

Review-Url: https://codereview.chromium.org/1962243002