DRTVWR-559 Optimization pass, make it so profileAvatar can read back GPU timer without a frame stall.

SL-19656 Rewrite avatar and attachment render metrics to not interfere with render pipe and be representative of actual render cost instead of driver synchronization time.

* SL-19656 Rewrite avatar and attachment render metrics to not interfere with render pipe and be representative of actual render cost instead of driver synchronization time.

* SL-19656 Remove now dead code (trackAttachments et al).

* SL-19656 Fix for crash on GL <= 3.2

SL-19644: Move GLTF transform reset out of pushBatch

DRTVWR-559 Touch up performance floater graphics preferences to remove preferences that no longer exist.

DRTVWR-559 merge 539

Has to use class1 now since class0 shouldn't ever be in use on
end-user systems anymore.

Reduce memory bandwith pressure during full screen post process passes. Incidental decrufting along the way

SL-19653: Fix some vertex buffer data mask asserts