[One .NET] specify all RIDs by default

[jonathanpeppers]

Fixes: https://devdiv.visualstudio.com/DevDiv/_workitems/edit/1413756
Fixes: #6353

The API 31 emulator no longer has 32-bit images and the x86_64 image
has dropped support for 32-bit architectures:

> adb shell getprop | grep cpu
[ro.product.cpu.abi]: [x86_64]
[ro.product.cpu.abilist]: [x86_64,arm64-v8a]
[ro.product.cpu.abilist32]: []
[ro.product.cpu.abilist64]: [x86_64,arm64-v8a]

Compared to an API 30 x86_64 emulator:

> adb shell getprop | grep cpu
[ro.product.cpu.abi]: [x86_64]
[ro.product.cpu.abilist]: [x86_64,x86,arm64-v8a,armeabi-v7a,armeabi]
[ro.product.cpu.abilist32]: [x86,armeabi-v7a,armeabi]
[ro.product.cpu.abilist64]: [x86_64,arm64-v8a]

The problem is our default RIDs are:

<RuntimeIdentifiers Condition=" '$(RuntimeIdentifier)' == '' And '$(RuntimeIdentifiers)' == '' ">android-arm64;android-x86</RuntimeIdentifiers>

And so you hit this error when trying to deploy a dotnet new android
app on an API 31 x86_64 emulator:

error ADB0020: Mono.AndroidTools.IncompatibleCpuAbiExceptiopn: The package does not support the CPU architecture of this device.

To workaround this, you can add android-x64 to your list of
$(RuntimeIdentifiers).

To solve this issue, we can default $(RuntimeIdentifiers) to all 4
architectures. We have code that will select a single architecture for
Debug builds using "Fast Deployment". It seems better to have a
default here that will always work, and the only drawback would be the
additional architectures for Release builds.

After this change, I discovered an issue introduced in 33a6d1e:

ILLink error IL1012: IL Linker has encountered an unexpected error. Please report the issue at https://github.com/mono/linker/issues [C:\a\_work\1\s\bin\TestRelease\temp\BuildProguard Enabled Project(1)Trued8r8\UnnamedProject.csproj]
...
Unhandled exception. System.IO.IOException: The process cannot access the file 'C:\a\_work\1\s\bin\TestRelease\temp\BuildProguard Enabled Project(1)Trued8r8\obj\Release\proguard\proguard_project_references.cfg' because it is being used by another process.

When we build each RID in parallel, each inner build was attempting to
write to the same file. I changed the path for this file to be:

$(IntermediateOutputPath)%(_RIDs.Identity)\proguard\proguard_project_references.cfg

And then set $(_ProguardProjectConfiguration) appropriately after
the inner builds complete. This also needs to actually be a file path,
I don't see how the value was working before:

<_ProguardProjectConfiguration Condition=" '$(AndroidLinkTool)' != '' ">;_ProguardProjectConfiguration=$(IntermediateOutputPath)proguard\proguard_project_references.cfg</_ProguardProjectConfiguration>

Then another related issue:

(_TouchAndroidLinkFlag target) ->
Microsoft.Android.Sdk.ILLink.targets(114,5): error MSB3371: The file "obj\Release\net6.0-android\link.flag" cannot be created. The process cannot access the file 'C:\a\_work\2\s\bin\TestRelease\temp\DotNetBuildandroid-armandroid-arm64android-x86android-x64TrueTrue\obj\Release\net6.0-android\link.flag' because it is being used by another process.

I setup $(_AndroidLinkFlag) the same as
$(_ProguardProjectConfiguration) to solve this issue.

[jonathanpeppers]

I think moving to 4 RIDs has triggered a problem on Windows:

ILLink error IL1012: IL Linker has encountered an unexpected error. Please report the issue at https://github.com/mono/linker/issues [C:\a\_work\1\s\bin\TestRelease\temp\BuildProguard Enabled Project(1)Trued8r8\UnnamedProject.csproj]
...
Unhandled exception. System.IO.IOException: The process cannot access the file 'C:\a\_work\1\s\bin\TestRelease\temp\BuildProguard Enabled Project(1)Trued8r8\obj\Release\proguard\proguard_project_references.cfg' because it is being used by another process.

Let me look into this.

[jonathanpeppers]

Another related error:

(_TouchAndroidLinkFlag target) -> 
Microsoft.Android.Sdk.ILLink.targets(114,5): error MSB3371: The file "obj\Release\net6.0-android\link.flag" cannot be created. The process cannot access the file 'C:\a\_work\2\s\bin\TestRelease\temp\DotNetBuildandroid-armandroid-arm64android-x86android-x64TrueTrue\obj\Release\net6.0-android\link.flag' because it is being used by another process.