This test suite was creating shm segments without ensuring they were
cleaned up. Shm segments outlive the process creating them, so on a
standard linux machine the test was leaving segments behind after each
run. This would often cause failures as test cases would be affected
by the cases that ran before them and left unexpected segments lying
around.
Also skip some assertions around memory usage when running on a Linux
host, as we can't reason about external users of shm segments.
PiperOrigin-RevId: 225435523
Change-Id: Ia299dacf59045002436f5e30dcc131f679bb7272
Rahat Mahmood
Brian Geffon