Add test/intrinsics/intrinsics.wgsl.tmpl that generates a vast set of intrinsic overload permutations into test/intrinsics/gen/...
Add expected output for all of these, including 'SKIP' headers for those that currently fail.
Fixed: tint:832
Change-Id: Id6888df52c07f35e7a55199f2ad4d842c6e2595c
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/53051
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: David Neto <dneto@google.com>