This is the HandleModuleScopeVars() part of the MSL sanitizer moved
verbatim to a standalone transform. The transform code is unchanged,
but some expected test outputs are different as this is now tested in
isolation instead of along with the rest of the sanitizer transforms.
This is step towards removing the sanitizers completely.
Change-Id: I7be826e2119451fc2ce2891740cc94f978e7d5a1
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/63583
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>