Traverse parent DexClassLoaders for native libraries in DelegateClassLoader

[Bencodes]

Fixes #13661 by traversing the class loaders looking for native libraries.

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[Bencodes]

cc: @ted-xie @ahumesky

[ted-xie]

Thanks for the PR, Ben! LGTM, I will push this through the internal tests.

[Bencodes]

@ted-xie I think this PR might be a better option to merge #15361

[ted-xie]

Oh, I didn't see your comment until now (after I've already merged this PR). I'll discuss with Alex.

[ted-xie]

@Bencodes @oliviernotteghem

Hi Ben,

Is there a particular reason you'd prefer #15361 over this PR (14965) that's already merged? From a quick glance at the code in #15361, there's no evident performance or functionality benefit. Additionally, this PR is much simpler (smaller, doesn't use reflection).

[Bencodes]

Oh, I didn't see your comment until now (after I've already merged this PR). I'll discuss with Alex.

This only fixes part of the issue where mobile install can't find native libraries. The pull request that @oliviernotteghem put up also addresses the reverse problem where native libraries need to call back into the JVM.

You can reproduce this using https://github.com/facebook/flipper. It's been a while since i've looked at their code but I believe this is where it will error out https://github.com/facebook/flipper/blob/main/android/src/main/cpp/sonar.cpp#L46-L48

[ted-xie]

Thanks for the information, Ben. I'll propose some next steps internally; will update the bug after that.