[external/Java.Interop] Remove standalone-repo scaffolding after merge

[jonathanpeppers]

Follow-up to #11942, which handles external/Java.Interop/.github/. This PR is round 2: delete files under external/Java.Interop/ that are byte-duplicates of top-level files, or orphans left over from the pre-merge standalone-repo layout.

Files deleted

File	Rationale
external/Java.Interop/product.snk	Byte-identical to top-level product.snk (SHA256 708EA5D6…AAB160).
external/Java.Interop/CODE-OF-CONDUCT.md	Identical 6-line boilerplate to top-level CODE-OF-CONDUCT.md.
external/Java.Interop/SECURITY.md	Near-duplicate of top-level SECURITY.md, with a stale link to the Xamarin support policy.
external/Java.Interop/.gitmodules	Redundant; the top-level .gitmodules already has the external/Java.Interop/external/xamarin-android-tools submodule entry.
external/Java.Interop/Java.Interop.code-workspace	6-line VS Code workspace file from the standalone repo, no references anywhere.
external/Java.Interop/Makefile	Standalone-repo GNU makefile. See "Makefile orphaned check" below.

product.snk retargeting

Nine JI csprojs previously set <AssemblyOriginatorKeyFile>..\..\product.snk</AssemblyOriginatorKeyFile> — resolving to external/Java.Interop/product.snk (the now-deleted duplicate). They now use a new shared property defined in external/Java.Interop/Directory.Build.props:

<ProductSnkPath Condition=" '$(ProductSnkPath)' == '' ">$(MSBuildThisFileDirectory)..\..\product.snk</ProductSnkPath>

which resolves to the top-level product.snk. Each of the 9 csprojs now says <AssemblyOriginatorKeyFile>$(ProductSnkPath)</AssemblyOriginatorKeyFile>.

Csprojs retargeted:

• src/Java.Interop/Java.Interop.csproj
• src/Java.Interop.Localization/Java.Interop.Localization.csproj
• src/Java.Interop.Tools.Cecil/Java.Interop.Tools.Cecil.csproj
• src/Java.Interop.Tools.Diagnostics/Java.Interop.Tools.Diagnostics.csproj
• src/Java.Interop.Tools.JavaCallableWrappers/Java.Interop.Tools.JavaCallableWrappers.csproj
• src/Java.Interop.Tools.Maven/Java.Interop.Tools.Maven.csproj
• src/Xamarin.Android.Tools.Bytecode/Xamarin.Android.Tools.Bytecode.csproj
• tests/Java.Interop-Tests/Java.Interop-Tests.csproj
• tests/TestJVM/TestJVM.csproj

Makefile orphaned check

Before deleting, I grepped the whole tree for callers of external/Java.Interop/Makefile:

• No matches for Java\.Interop.Makefile under top-level Makefile, build.sh, build.cmd, eng/, build-tools/, or Documentation/.
• No matches for make -C external/Java.Interop or make.*Java.Interop anywhere in the repo.
• Top-level CI drives JI via dotnet build external/Java.Interop/Java.Interop.sln (see external/Java.Interop/build-tools/automation/templates/core-build.yaml, referenced from build-tools/automation/yaml-templates/stage-java-interop-tests.yaml), never via make.

Verification

• dotnet msbuild external/Java.Interop/src/Java.Interop/Java.Interop.csproj -getProperty:AssemblyOriginatorKeyFile,ProductSnkPath reports both properties resolving to …\external\Java.Interop\..\..\product.snk (i.e. the top-level key).
• dotnet build external/Java.Interop/Java.Interop.sln -t:Prepare -c Debug — succeeds.
• dotnet build external/Java.Interop/src/Java.Interop/Java.Interop.csproj -c Debug — succeeds; the produced Java.Interop.dll reports the expected public key token 84e04ff9cfb79065.

Not in scope (deferred)

Flagged during the audit but left for follow-up PRs:

• Consolidating the nested external/Java.Interop/external/xamarin-android-tools submodule with the top-level external/xamarin-android-tools (still consumed by Java.Interop.sln, Java.Interop.BootstrapTasks.sln, and the CI templates).
• external/Java.Interop/.gitignore (only unique entries are obsolete Gendarme cruft and a specific dev's JDK installer package).
• README.md, LICENSE, ThirdPartyNotices.txt — need TPN / legal review before merging into top-level equivalents.
• .editorconfig / .gitattributes — nearly identical to top-level; the JI .gitattributes uniquely covers gradlew / *.properties / *.kt / *.kts for build-tools/gradle/. Harmless as-is.

---

Pull Request
title and
description
should follow the
commit-messages.md workflow documentation, and in particular should include:

• Useful description of why the change is necessary.
• Links to issues fixed — n/a, follow-up to Merge Java.Interop .github/ into dotnet/android after repo unification #11942.
• Unit tests — n/a for a delete-only cleanup; verified locally by building the signed Java.Interop.csproj and confirming the public-key token.

[Copilot]

Pull request overview

Removes leftover standalone-repo scaffolding under external/Java.Interop/ after the Java.Interop merge, and retargets Java.Interop project signing to use the repo-root product.snk rather than a duplicated copy.

Changes:

• Introduces $(ProductSnkPath) in external/Java.Interop/Directory.Build.props pointing to the repo-root product.snk.
• Updates 9 Java.Interop projects/tests to sign using $(ProductSnkPath) instead of a relative path to a now-deleted duplicate key.
• Deletes redundant/orphaned standalone-repo files (SECURITY.md, CODE-OF-CONDUCT.md, nested .gitmodules, Makefile, VS Code workspace).

Reviewed changes

Copilot reviewed 15 out of 16 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
external/Java.Interop/Directory.Build.props	Adds ProductSnkPath property resolving to repo-root product.snk.
external/Java.Interop/src/Java.Interop/Java.Interop.csproj	Uses $(ProductSnkPath) for AssemblyOriginatorKeyFile.
external/Java.Interop/src/Java.Interop.Localization/Java.Interop.Localization.csproj	Uses $(ProductSnkPath) for signing key.
external/Java.Interop/src/Java.Interop.Tools.Cecil/Java.Interop.Tools.Cecil.csproj	Uses $(ProductSnkPath) for signing key.
external/Java.Interop/src/Java.Interop.Tools.Diagnostics/Java.Interop.Tools.Diagnostics.csproj	Uses $(ProductSnkPath) for signing key.
external/Java.Interop/src/Java.Interop.Tools.JavaCallableWrappers/Java.Interop.Tools.JavaCallableWrappers.csproj	Uses $(ProductSnkPath) for signing key.
external/Java.Interop/src/Java.Interop.Tools.Maven/Java.Interop.Tools.Maven.csproj	Uses $(ProductSnkPath) for signing key.
external/Java.Interop/src/Xamarin.Android.Tools.Bytecode/Xamarin.Android.Tools.Bytecode.csproj	Uses $(ProductSnkPath) for signing key.
external/Java.Interop/tests/Java.Interop-Tests/Java.Interop-Tests.csproj	Uses $(ProductSnkPath) for signing key.
external/Java.Interop/tests/TestJVM/TestJVM.csproj	Uses $(ProductSnkPath) for signing key.
external/Java.Interop/SECURITY.md	Deleted redundant/stale security policy file.
external/Java.Interop/CODE-OF-CONDUCT.md	Deleted duplicate Code of Conduct file.
external/Java.Interop/.gitmodules	Deleted redundant nested .gitmodules.
external/Java.Interop/Java.Interop.code-workspace	Deleted orphaned VS Code workspace file.
external/Java.Interop/Makefile	Deleted orphaned standalone-repo Makefile.