Simpleperf: fix flaky workload unit tests.

Move SIGABRT to SIGKILL to make sure the child process is terminated by a signal.
SIGABRT can't guarantee this because the child process can install signal handler for SIGABRT.

Add a final _exit(1) after ChildProcessFn in case execvp() fails.

Change-Id: I353720b10c6ea42826efcafce5ff2699fd246e22
2 files changed