i.e. #ifndef VM_WHATEVER -> #ifndef RUNTIME_VM_WHATEVER
This lets us remove a hack from the PRESUBMIT.py script that existed
for reasons that are no longer valid, and sets us up to add some
presubmit checks for the GN build.
R=asiva@google.com, rmacnak@google.com
Review URL: https://codereview.chromium.org/2450713004 .
Fuchsia provides pthreads so the linux implementation almost works
except that fuchsia does not (currently) provide the clock_gettime clock
for CLOCK_THREAD_CPUTIME_ID.
Review URL: https://codereview.chromium.org/2154453002 .
Ryan Macnak