UniqueIdentifier() will generate a program-global unique symbol.
MslGeneratorImplTest.AttemptTintPadSymbolCollision tests for collisions with the field names.
TextGeneratorTest.UniqueIdentifier_ConflictWithExisting tests for collisions between general symbols.
Fixed: tint:654
Change-Id: If2ba75d04ff0e2a9975e878596ac114d51adcd46
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/56580
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Sarah Mashayekhi <sarahmashay@google.com>
Reviewed-by: James Price <jrprice@google.com>
Commit-Queue: James Price <jrprice@google.com>
Auto-Submit: Ben Clayton <bclayton@google.com>
885488da41