Remove unnecessary Unsafe.As call from StringValues

[GrabYourPitchforks]

(Caught by static analysis.)

This is essentially calling Unsafe.As<string>(string), which is a no-op. Remove the call to Unsafe.As.

Copilot reviewed 1 out of 1 changed files in this pull request and generated no comments.

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[EgorBo]

Other Unsafe.As look also a bit unnecessary there as well, cast from object to string or string[] is as cheap as

       mov      rcx, 0x7FF89056B608      ; System.String[]
       cmp      qword ptr [rax], rcx
       je       SHORT G_M23900_IG07

[lewing]

/ba-g the server2025 failures were due to an ES rollout

[GrabYourPitchforks]

Other Unsafe.As look also a bit unnecessary there as well, cast from object to string or string[] is as cheap as

       mov      rcx, 0x7FF89056B608      ; System.String[]
       cmp      qword ptr [rax], rcx
       je       SHORT G_M23900_IG07

@EgorBo I agree it would be worth changing that as part of a larger effort to remove use of unsafe code where it's not giving a meaningful benefit. But I figured this one-line change would be uncontroversial because the use of unsafe code in this instance can be shown to provide zero benefit. :)

[stephentoub]

Other Unsafe.As look also a bit unnecessary there as well, cast from object to string or string[] is as cheap as

I agree it would be worth changing that as part of a larger effort to remove use of unsafe code where it's not giving a meaningful benefit.

I would not be surprised if changing this to a real cast showed up on ASP.NET benchmarks, as I understand this to be on some critical paths.

If it doesn't affect any ASP.NET benchmarks, sure, kill it.