Fix illumos compile error in coreclr/vm/appdomain.hpp

[gwr]

Using gcc 13.3 configured as a cross-compiler:

$ /crossrootfs/x64/bin/x86_64-illumos-gcc --version
x86_64-illumos-gcc (GCC) 13.3.0
Copyright (C) 2023 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

There are Wchanges-meaning errors in src/coreclr/vm/appdomain.hpp

src/coreclr/vm/appdomain.hpp:1934:40: error: declaration of 'constexpr SystemDomain** const cdac_data<SystemDomain>::SystemDomain' changes meaning of 'SystemDomain' [-Wchanges-meaning]
   1934 |     static constexpr PTR_SystemDomain* SystemDomain = &SystemDomain::m_pSystemDomain;
        |                                        ^~~~~~~~~~~~
  src/coreclr/vm/appdomain.hpp:1934:56: note: used here to mean 'class SystemDomain'
   1934 |     static constexpr PTR_SystemDomain* SystemDomain = &SystemDomain::m_pSystemDomain;
        |                                                        ^~~~~~~~~~~~
  src/coreclr/vm/appdomain.hpp:1629:7: note: declared here
   1629 | class SystemDomain final
        |       ^~~~~~~~~~~~

What I read about Wchanges-meaning errors recommends renaming one of the things in conflict to avoid the problem, which is what this change does. Is this OK?
I'm not sure about this fix, but it let things build for me.

FWIW, the change here is similar to how other problems were fixed in 3099f31

[gwr]

The CI for this is showing a Pri0 test failure:
runtime (Build coreclr Pri0 Runtime Tests Run linux x64 checked)

but the details suggest this is browser/wasm stuff again

  ninja: build stopped: subcommand failed.
##[error]BUILD: Error: native component build failed. Refer to the build log files for details.
      "D:\a\_work\1\s\artifacts\log\Release\CoreCLR_browser__wasm__Release__wasm.log"
      "D:\a\_work\1\s\artifacts\log\Release\CoreCLR_browser__wasm__Release__wasm.wrn"
      "D:\a\_work\1\s\artifacts\log\Release\CoreCLR_browser__wasm__Release__wasm.err"
D:\a\_work\1\s\src\coreclr\runtime.proj(117,5): error MSB3073: The command ""D:\a\_work\1\s\src\mono\browser\emsdk\emsdk_env.cmd" && D:\a\_work\1\s\src\coreclr\"build-runtime.cmd" -wasm -release -ci -os browser -targetrid browser-wasm -cmakeargs "-DCLR_DOTNET_RID=browser-wasm" -cmakeargs "-DCLR_DOTNET_HOST_PATH=D:\a\_work\1\s\.dotnet\dotnet.exe" -cmakeargs "-DCDAC_BUILD_TOOL_BINARY_PATH=D:\a\_work\1\s\artifacts\bin\coreclr\browser.wasm.Release\cdac-build-tool\cdac-build-tool.dll" -cmakeargs "-DCLR_CMAKE_ICU_DIR=D:\a\_work\1\s\.packages\microsoft.netcore.runtime.icu.transport\10.0.0-preview.6.25302.1/runtimes/browser-wasm/native" -component runtime -keepnativesymbols" exited with code 1.
##[error]src\coreclr\runtime.proj(117,5): error MSB3073: (NETCORE_ENGINEERING_TELEMETRY=Build) The command ""D:\a\_work\1\s\src\mono\browser\emsdk\emsdk_env.cmd" && D:\a\_work\1\s\src\coreclr\"build-runtime.cmd" -wasm -release -ci -os browser -targetrid browser-wasm -cmakeargs "-DCLR_DOTNET_RID=browser-wasm" -cmakeargs "-DCLR_DOTNET_HOST_PATH=D:\a\_work\1\s\.dotnet\dotnet.exe" -cmakeargs "-DCDAC_BUILD_TOOL_BINARY_PATH=D:\a\_work\1\s\artifacts\bin\coreclr\browser.wasm.Release\cdac-build-tool\cdac-build-tool.dll" -cmakeargs "-DCLR_CMAKE_ICU_DIR=D:\a\_work\1\s\.packages\microsoft.netcore.runtime.icu.transport\10.0.0-preview.6.25302.1/runtimes/browser-wasm/native" -component runtime -keepnativesymbols" exited with code 1.

Is this something I need to fix?

[jkotas]

/ba-g Known wasm build error