Reland "Reland: [skslc] Generate .hlsl test output files"

Reland with fixed gni_exporter.go

Bug: skia:12691, skia:12352

Description of original change:
> This is a reland of a change originally reviewed on
> https://skia-review.googlesource.com/c/skia/+/482778.
>
> - The build now generates HLSL output when `skia_compile_sksl_tests` is
> enabled.
> - The "blend" and "shared" tests have been enabled for HLSL with the
> exception of 6 tests that exercise intrinsic inverse hyperbolic
> functions, which don't have HLSL equivalents.
>
> Bug: skia:12691, skia:12352
> Change-Id: I7188b75dcdec5edffe60004b283ba84e3ac16fc1
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/609218
> Reviewed-by: Brian Osman <brianosman@google.com>
> Commit-Queue: Arman Uguray <armansito@google.com>

Change-Id: I8b0b59a7d85303fee5bf5488b4e552af635473e0
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/609698
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Arman Uguray <armansito@google.com>
280 files changed