Support CRaC with Java agents that use appendToBootstrapClassLoaderSearch

[mcculls]

Instrumentation.appendToBootstrapClassLoaderSearch(jarfile) ends up creating a file descriptor for the jarfile in native code that cannot be closed or claimed from Java:

https://github.com/openjdk/jdk/blob/jdk-25%2B2/src/hotspot/share/prims/jvmtiEnv.cpp#L671

These FDs can be ignored and left to the CRaC engine.

Without this change you cannot use CRaC with Java agents that call appendToBootstrapClassLoaderSearch, unless you use -XX:CRAllowedOpenFilePrefixes as a workaround.

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Progress

• Change must not contain extraneous whitespace

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[bridgekeeper]

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[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[rvansa]

Hi @mcculls , the fix looks good - do you think you could accompany it with a test case?

[mcculls]

Hi @rvansa - yes I can add a test case

[mcculls]

/covered

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