Change asan/TestCases/Darwin/malloc_zone-protected.cpp to call abort so that it always crashes.
This is needed because on some platforms we can't install signal
handlers and so the application just traps (i.e. crashes) rather than being intercepted
by ASan's signal handler which in the default Darwin config doesn't
exit with a crashing exit code.
Reviewers: yln, kubamracek, jfb
Subscribers: #sanitizers, llvm-commits
Tags: #sanitizers, #llvm
Differential Revision: https://reviews.llvm.org/D71573