Previously nested scopes would hide their parent variables.
This is no longer the case.

Bug: b/148401179
Change-Id: Icf2771a525524b8796ab12e295e141388bb5b399
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/42368
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Tested-by: Ben Clayton <bclayton@google.com>