[xaprepare] Delete redundant Windows JdkInfo.props generator

[jonathanpeppers]

Summary

On Windows, xaprepare's Step_GenerateFiles.Windows.cs writes external/Java.Interop/bin/Build$(Configuration)/JdkInfo.props from build-tools/xaprepare/xaprepare/Resources/JdkInfo.Windows.props.in.

But this file is immediately overwritten. The PrepareWindows.targets Prepare flow runs, in order:

1. dotnet xaprepare -a — writes JdkInfo.props (this code).
2. MSBuild Xamarin.Android.BootstrapTasks.sln — does not read JdkInfo.props.
3. MSBuild src/workloads/workloads.csproj — does not read JdkInfo.props.
4. CallTarget PrepareJavaInterop → dotnet build -t:Prepare Java.Interop.sln → external/Java.Interop/build-tools/scripts/Prepare.targets → runs the JdkInfo MSBuild task → overwrites JdkInfo.props with its own generated content.

Nothing between step 1 and step 4 reads the file, and Java.Interop's Prepare always regenerates it. Now that external/Java.Interop is in-tree, we can safely delete the redundant write.

Files touched

• Delete build-tools/xaprepare/xaprepare/Steps/Step_GenerateFiles.Windows.cs
• Delete build-tools/xaprepare/xaprepare/Resources/JdkInfo.Windows.props.in
• Edit build-tools/xaprepare/xaprepare/Steps/Step_GenerateFiles.cs — drop the partial void AddOSSpecificSteps declaration and collapse GetFilesToGenerate so atBuildStart == false returns null. Ctor surface (atBuildStart, onlyRequired) is unchanged so Scenario_Required.cs is unaffected.
• Edit build-tools/xaprepare/xaprepare/Scenarios/Scenario_Standard.cs — remove the AddEndSteps override; the only thing it did was schedule the now-empty Step_GenerateFiles(atBuildStart: false).

Preserved (future slices will address these):

• Get_Configuration_OperatingSystem_props (D1).
• OperatingSystems/*.cs and Context.OS.* surface.
• PrepareWindows.targets, DotNet.targets, Java.Interop's Prepare.targets.

Diff: 4 files changed, 5 insertions(+), 82 deletions(-).

Verification

1. dotnet build build-tools/xaprepare/xaprepare/xaprepare.csproj -c Debug → Build succeeded. 0 Warning(s). 0 Error(s).

2. build.cmd -t:Prepare -c Debug (Windows, cold tree) — succeeds; external/Java.Interop/bin/BuildDebug/JdkInfo.props exists.

3. Compare-Object of the resulting JdkInfo.props before vs after this change — byte-identical:

   Baseline SHA256: DE59A8061B7657831788FFED7BC1DEECA442E9181605083A4553DE7AC8C003A1  (1493 bytes)
   After    SHA256: DE59A8061B7657831788FFED7BC1DEECA442E9181605083A4553DE7AC8C003A1  (1493 bytes)
   Compare-Object result: (no differences)
   

   This confirms Java.Interop's overwrite is what always ends up on disk.

4. Grep audit under build-tools/xaprepare/: no remaining references to Step_GenerateFiles.Windows, JdkInfo.Windows.props.in, or AddOSSpecificSteps.

Related PRs

Follows previous xaprepare deletion slices #11568, #11580, #11608, #11613, #11631, #11731, #11732, #11733, #11737, #11740, #11760, #11803, #11821, #11825, #11826.

[Copilot]

Pull request overview

Removes xaprepare’s redundant Windows-only generation of external/Java.Interop/bin/Build$(Configuration)/JdkInfo.props, since Java.Interop’s own Prepare flow reliably regenerates (and overwrites) the file later in the prepare pipeline.

Changes:

• Deleted the Windows-specific Step_GenerateFiles partial that generated JdkInfo.props.
• Deleted the corresponding JdkInfo.Windows.props.in template resource.
• Simplified Step_GenerateFiles and Scenario_Standard to stop scheduling the now-empty “end” generation step and to return null when atBuildStart == false.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
build-tools/xaprepare/xaprepare/Steps/Step_GenerateFiles.Windows.cs	Deleted the Windows-only generator that produced JdkInfo.props.
build-tools/xaprepare/xaprepare/Steps/Step_GenerateFiles.cs	Removed OS-specific partial plumbing and simplified generation to only run at build start.
build-tools/xaprepare/xaprepare/Scenarios/Scenario_Standard.cs	Removed the end-of-scenario Step_GenerateFiles(atBuildStart: false) scheduling.
build-tools/xaprepare/xaprepare/Resources/JdkInfo.Windows.props.in	Deleted the unused template that previously fed the Windows generator.