[Tests] Remove Builder.UseDotNet

[pjcollins]

The .NET versus Classic switches have been removed from the MSBuild
tests. Tests / asserts that only applied to classic have been removed.
Test parameters that only applied to classic (aapt vs aapt2) have
been removed. Some project properties that only applied to classic
(UseLatestPlatformSdk) have been removed.

[pjcollins]

This should be ready for review. Since there is a lot changing/being removed here we may want to hold off on merging for a little while however, if only to make any upcoming backports needed for .NET 8 easier.

[jonathanpeppers]

I got partway through...

As for concerns about conflicts, I would be ok just taking this back to .NET 8 servicing. It's test-only changes, and shouldn't break anything.

[pjcollins]

There's one issue that's been happening here consistently that I can't seem to track down, and couldn't repro locally:

 Failed RunWithLLVMEnabled [1 m 41 s]
  Error Message:
     LLVM .so files not loaded:
10-25 19:11:59.456  7936  7936 I monodroid-assembly: Failed to load shared library '/data/app/com.xamarin.runwithllvmenabled-yiFod3LQK46wSU9vJ8UUfw==/split_config.x86_64.apk!/lib/x86_64/libmono-profiler-aot.so'. dlopen failed: library "/data/app/com.xamarin.runwithllvmenabled-yiFod3LQK46wSU9vJ8UUfw==/split_config.x86_64.apk!/lib/x86_64/libmono-profiler-aot.so" not found
10-25 19:11:59.456  7936  7936 I monodroid-assembly: Failed to load shared library '/data/app/com.xamarin.runwithllvmenabled-yiFod3LQK46wSU9vJ8UUfw==/lib/x86_64/libmono-profiler-aot.so'. dlopen failed: library "/data/app/com.xamarin.runwithllvmenabled-yiFod3LQK46wSU9vJ8UUfw==/lib/x86_64/libmono-profiler-aot.so" not found
  Expected: 0
  But was:  2

I don't think a version of libmono-profiler-aot.so exists for .NET Android? @grendello do you have any thoughts as to why we're trying to load this?

[jonathanpeppers]

libmono-profiler-aot.so would only exist in .NET 6+, if you added my NuGet package:

https://www.nuget.org/packages/Mono.AotProfiler.Android

[grendello]

@pjcollins we'd load it if the debug.mono.profile sysprop were set to contain something like e.g. aot:output=file/path

[pjcollins]

@pjcollins we'd load it if the debug.mono.profile sysprop were set to contain something like e.g. aot:output=file/path

Ooh great thanks, I think this explains it. It looks like this test is running during the same job as BuildBasicApplicationAndAotProfileIt now, so I'll update that fixture to make sure we clear the profiling prop.

[pjcollins]

I think this should be good to go whenever there's some time to review.

[pjcollins]

Not yet sure what's up with the latest resource designer test failures but they seem to be happening on other PRs, and I haven't been able to repro them locally.

[dellis1972]

@pjcollins the designer tests have been fixed, if you rebase they should go away 👍