Geometry offset attribute cleanup

[hpinkos]

Cleanup from #6607

• Fix IE by passing the offsetAttribute through to the geometry instead of searching through the applyOffset per vertex to figure out if the geometry was using GeometryOffsetAttribute.TOP
• Fix bounding sphere when using GeometryOffsetAttribute.NONE
• Fix bounding sphere when retrieving it from the geometry instance batch table
• Fix crash if instance attribute was undefined
  • ie. attributes : { color : colorAttribute, offset : undefined } instead of attributes : {color : colorAttribute}

[mramato]

@bagnell can you take a look at this?

[hpinkos]

One sec, I fixed this for synchornous primitives but not asynchronous

[hpinkos]

@bagnell this is ready for a full review now. Thanks!

[bagnell]

👍