Fix Draco decoding for vertex colors that are normalized UNSIGNED_BYTE or UNSIGNED_SHORT

[lilleyse]

Description

The draco decoder incorrectly decodes vertex colors that are normalized UNSIGNED_BYTE or UNSIGNED_SHORT.

The fix is to not hardcode attributesToSkip in decodeDraco. If vertex colors were originally normalized UNSIGNED_BYTE or UNSIGNED_SHORT and the attribute transform is skipped they will be read as an unnormalized INT instead of normalized UNSIGNED_BYTE or UNSIGNED_SHORT. So the fix is to only skip the attribute transform if the vertex colors were quantized from FLOAT.

Most of the other changes are passing primitive to GltfDracoDecoder.

Before	After

Issue number and link

Testing plan

See this sandcastle that loads two tilesets, one with normalized UNSIGNED_BYTE vertex colors, and another with FLOAT vertex colors. The first tileset looks incorrect in main and correct on this branch. The second tileset looks correct on both.

I spot checked a few other sandcastle that have Draco compressed models like Google 3D Tiles and the Montreal Point Cloud and those still seem fine.

Author checklist

• I have submitted a Contributor License Agreement
• I have added my name to CONTRIBUTORS.md
• I have updated CHANGES.md with a short summary of my change
• I have added or updated unit tests to ensure consistent code coverage
• I have updated the inline documentation, and included code examples where relevant
• I have performed a self-review of my code

[github-actions]

Thank you for the pull request, @lilleyse!

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