MSBuild should respect upstream tool language requests

Different upstream tools have different language configuration requirements:

• dotnet CLI sets DOTNET_CLI_UI_LANGUAGE and VSLANG (https://github.com/Microsoft/msbuild/issues/1596#issuecomment-409362785 https://github.com/dotnet/cli/issues/9722#issuecomment-409358296)
• Visual Studio has a fallback mechanism guideline. In order:
  • VSLANG environmnent variable
  • /lcid command line switch
  • call GetConsoleFallbackUICulture (we only do this currently)

Related info: https://github.com/dotnet/cli/issues/4988#issuecomment-266836559

[nagilson]

This should be added & fixed in 8.0 preview 5!

[chylex]

@hcoona I will add that you can usually search for the error code and copy the actual English error from Microsoft’s documentation, which sounds like it would not be a lot of extra steps, but in reality it goes more like this:

1. Search the error code on Google.
2. Visit a Microsoft documentation page for the error.
3. Be automatically redirected to a localized version of the documentation. I’m not sure about compiler errors specifically, but most times these “localized” documentation pages are actually machine-translated, which means there are many grammatical errors and mistranslations which actively harm the understandability of your documentation for foreigners.
4. Manually switch the website language to English.
5. Finally you can copy/paste the actual error message into Google.

I’m sorry, but this whole thing is a terrible user experience.