[compiler-rt] [scudo] Enable "Delayed release to OS" feature for Android (PR #65942)

[Mitch Phillips via llvm-commits]

hctim wrote:

Circling back on this - GB (the way that we run it, and so do others on the device-side team) is to use a dynamically-linked gb executable that runs with the device's libc/libm/etc.

Given that we see a major source of overhead from the secondary, I think it might be worth changing the Android secondary allocator config `ReleaseToOsIntervalMs` from zero -> non-zero. I'm running some experiments using the normal way I execute to corroborate results.

I don't think it's worth going the full hog and creating an API to control the interval for primary/secondary individually (and then plumb it through to some `M_PURGE_LARGE` or something silly), but setting the default to non-zero might have some positive effects here.

I'm not exactly sure how to measure the increased PSS though. Any ideas?

https://github.com/llvm/llvm-project/pull/65942