A lot of these benchmarks predate DoNotOptimize and rolled their own
hacks.
Bug: http://b/148307629
Test: ran benchmarks before & after and got similar results
Change-Id: If44699d261b687f6253af709edda58f4c90fb285
Add benchmarks for mallinfo, and for retrieving RSS from
/proc/self/statm, since we're considering using these for GC
triggering.
Add some static linkage specifiers, after running into a build
problem due to a spurious conflict.
Bug: 111447610
Test: Ran benchmarks
Change-Id: Ie50d512294993882728c63ce51ec507590257d80