[android] Investigate using different GC variants with CoreCLR on Android

[ivanpovazan]

Description

This is a tracking issue for investigation work on potential benefits of different GC variants on Android:

• Investigate what tuning parameters we should adjust for regions GC for mobile ref
• Investigate using server GC for Android apps ref
• TBD - any other potential benefit

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[Maoni0]

instead of investigating whether we should use segments GC vs regions GC, I would put "investigate what tuning parameters we should adjust for regions GC for mobile". for example, one obvious thing to adjust is the region size - the default is 4mb, for small heaps you could totally adjust this down to 1mb.

the reason why I would not investigate using segments GC to begin with is it's something we are hoping to phase out so fixing bugs in it is inefficient (it just takes care of a small percentage of scenarios that still use it) and there will be fewer and fewer engineers with even knowledge about it.