MDC-Android ShapeAppearanceModel instantiation

mdc_sam_instantiation.kt

/* Copyright 2020 Google LLC.
   SPDX-License-Identifier: Apache-2.0 */

// Default builder
val sam = ShapeAppearanceModel.builder()
    .setAllCorners(CornerFamily.CUT, cornerSize)
    // Also setTopRightCorner, setAllEdges, etc.
    .build()
// Style/attr resources builder (reads shapeAppearance and shapeAppearanceOverlay)
val samFromStyles = ShapeAppearanceModel.builder(context, attrs, defStyleAttr, defStyleRes)
    .build()
// Build from existing ShapeAppearanceModel
val samFromExisting = sam.toBuilder()
    ...
    .build()