[xaprepare] Move Configuration.OperatingSystem.props JDK values to JdkInfo.props

[jonathanpeppers]

Summary

JDK-related properties are now sourced from Java.Interop's JdkInfo MSBuild task (in-tree since #11744) plus Configuration.props. The Configuration.OperatingSystem.props generator in xaprepare no longer writes any JDK values — only the NDK/OS-info half remains, which will be removed in a follow-up slice.

Changes

• Configuration.props
  • Imports external\Java.Interop\bin\Build$(Configuration)\JdkInfo.props immediately after Configuration.OperatingSystem.props. Java.Interop supplies JavaSdkDirectory, JavaPath, JavaCPath, JarPath (plus additional JDK metadata) once Prepare has run.
  • Sets JavaSdkVersion (= $(MicrosoftOpenJDKVersion)) and MinimumSupportedJavaSdkVersion (= 17.0) directly, since JdkInfo.props does not emit those two policy constants.
  • Adds conditional JavaPath, JavaCPath, JarPath fallbacks derived from $(JavaSdkDirectory)\bin\{tool}{.exe on Windows} — mirroring what xaprepare's OS.cs computed pre-slice. This ensures those properties are always defined for consumers that read them directly (e.g. src/Mono.Android/Mono.Android.targets, build-tools/scripts/JavaCallableWrappers.targets, src/java-runtime/java-runtime.targets, build-tools/create-android-api/create-android-api.csproj) even before PrepareJavaInterop has generated JdkInfo.props. When JdkInfo.props is imported, its conditional values win.
• build-tools/xaprepare/xaprepare/Resources/Configuration.OperatingSystem.props.in — removes JavaSdkVersion, MinimumSupportedJavaSdkVersion, JavaSdkDirectory, JavaCPath, JarPath, JavaPath.
• build-tools/xaprepare/xaprepare/Steps/Step_GenerateFiles.cs — removes the six matching entries from the replacements dictionary.
• build-tools/xaprepare/xaprepare/ConfigAndData/Configurables.cs — deletes now-dead MicrosoftOpenJDKVersion (const string + Version field) and MicrosoftMinOpenJDKVersion. Grep confirms zero remaining consumers under build-tools/xaprepare.

OS.JavaHome/JavaCPath/JavaPath/JarPath are intentionally left in place — Windows.cs still uses JavaHome for the JAVA_HOME env var. Removing those OS discovery paths is deferred to the next slice.

Verification

xaprepare build: dotnet build build-tools\xaprepare\xaprepare\xaprepare.csproj -c Debug → 0 warnings, 0 errors.

Effective-value verification — three states via a probe project that imports Configuration.props with AndroidToolchainDirectory=C:\android-toolchain:

Pre-slice equivalent (simulated Configuration.OperatingSystem.props present, no JdkInfo.props):

JavaSdkVersion=21.0.8
MinimumSupportedJavaSdkVersion=17.0
JavaSdkDirectory=C:\jdk-21
JavaCPath=C:\jdk-21\bin\javac.exe
JarPath=C:\jdk-21\bin\jar.exe
JavaPath=C:\jdk-21\bin\java.exe

Post-slice, fresh clone (no Configuration.OperatingSystem.props, no JdkInfo.props — fallbacks fire):

JavaSdkVersion=21.0.8
MinimumSupportedJavaSdkVersion=17.0
JavaSdkDirectory=C:\android-toolchain\jdk-21
JavaCPath=C:\android-toolchain\jdk-21\bin\javac.exe
JarPath=C:\android-toolchain\jdk-21\bin\jar.exe
JavaPath=C:\android-toolchain\jdk-21\bin\java.exe

Post-slice, post-Prepare (with JdkInfo.props supplying real paths):

JavaSdkVersion=21.0.8
MinimumSupportedJavaSdkVersion=17.0
JavaSdkDirectory=D:\real-jdk\jdk-21
JavaCPath=D:\real-jdk\jdk-21\bin\javac.exe
JarPath=D:\real-jdk\jdk-21\bin\jar.exe
JavaPath=D:\real-jdk\jdk-21\bin\java.exe

Grep audit under build-tools/xaprepare/: zero references to @JAVA_SDK_VERSION@, @MIN_SUPPORTED_JDK_VERSION@, @javac@, @java@, @jar@, MicrosoftOpenJDKVersion, or MicrosoftMinOpenJDKVersion remain. @JavaSdkDirectory@ still appears in xaprepare.targets / Properties.Defaults.cs.in — that's the unrelated compile-time replacement in Properties.Defaults.cs, intentionally left alone.

Cold -t:Prepare was not run in this environment (no Android toolchain / network); the fallback logic above ensures behavior is well-defined in every state along the Prepare pipeline.

File list

File	+/-
Configuration.props	+10
build-tools/xaprepare/xaprepare/ConfigAndData/Configurables.cs	−5
build-tools/xaprepare/xaprepare/Resources/Configuration.OperatingSystem.props.in	−6
build-tools/xaprepare/xaprepare/Steps/Step_GenerateFiles.cs	−6

Net: +10 / −17 (−7 LOC).

Precedent

Continues the incremental xaprepare removal in #11568, #11580, #11608, #11613, #11631, #11731, #11732, #11733, #11737, #11740, #11760, #11803, #11821, #11825, #11826, #11945, #11946.

[Copilot]

Pull request overview

Moves JDK-related MSBuild properties out of xaprepare’s generated Configuration.OperatingSystem.props and into the Java.Interop-generated JdkInfo.props, reducing xaprepare’s responsibility to OS/NDK-related values while keeping the overall Configuration.props import chain intact.

Changes:

• Import external/Java.Interop/bin/Build$(Configuration)/JdkInfo.props from Configuration.props (when present) and define JDK policy constants (JavaSdkVersion, MinimumSupportedJavaSdkVersion) directly in Configuration.props.
• Remove JDK placeholders and replacements from the xaprepare Configuration.OperatingSystem.props template and generator.
• Delete now-dead Microsoft OpenJDK version constants from xaprepare configurables.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
Configuration.props	Imports Java.Interop-generated JdkInfo.props and defines JavaSdkVersion / minimum supported JDK policy.
build-tools/xaprepare/xaprepare/Steps/Step_GenerateFiles.cs	Stops emitting JDK-related placeholder replacements for the OS props generator.
build-tools/xaprepare/xaprepare/Resources/Configuration.OperatingSystem.props.in	Removes JDK-related properties from the generated OS props template.
build-tools/xaprepare/xaprepare/ConfigAndData/Configurables.cs	Removes unused JDK version/minimum constants from xaprepare defaults.