tree fe6c1efb476e6b53247fc79c062f9c6044403d81
parent fdc32e2015023fa406c4228a6a6df412f6dbcf72
author Peter McNeeley <petermcneeley@google.com> 1732653810 +0000
committer Dawn LUCI CQ <dawn-scoped@luci-project-accounts.iam.gserviceaccount.com> 1732653810 +0000

[tint] Allow platform discard on metal >= 2.3

For Metal 2.3+ the discard semantics have changed to demote to
helper. This means we no longer need to run our own demote to helper
internal transformation.

This feature is tested by both CTS and the dawn_end2end
`DiscardBasicTest`


Platform Discard document:
https://docs.google.com/document/d/1CEnS-99jspI-ghs_wOpZ8vMGhOW80wQxxTDly87bFN4/edit?pli=1&resourcekey=0-o02HubN1NPVz1ssuEyqIPQ&tab=t.0

Metal 2.3 version:
https://developer.apple.com/documentation/metal/mtllanguageversion/mtllanguageversion2_3

Bug: 42250787, 372714384
Change-Id: Icbb56f8a08b35178283104b3ae7c2ad53c479e16
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/216497
Commit-Queue: Peter McNeeley <petermcneeley@google.com>
Reviewed-by: James Price <jrprice@google.com>