Make run.py more compatible with the 'perf' command.
Make run.py more compatible with the 'perf' command.

Adds NACL_FAULT_INJECTION=ELF_LOAD_BYPASS_DESCRIPTOR_SAFETY_CHECK=GF1/999 to the environment to enable mmap() for loading the nexe.  This allows "perf record run.py my.nexe" to report usable results.

This is suppressed when the "--paranoid" option is used.

BUG= https://bugs.chromium.org/p/nativeclient/issues/detail?id=4360
R=mseaborn@chromium.org

Review URL: https://codereview.chromium.org/1778363002 .

sbc100/native_client,sbc100/native_client,sbc100/native_client,sbc100/native_client,sbc100/native_client,sbc100/native_client