[msan] Lit tests for __attribute__((no_sanitize_memory)).


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@176248 91177308-0d34-0410-b5e6-96231b3b80d8
[Sanitizer] Relax ThreadLister tests to allow possible pre-existing threads. Do proper mutex destruction. Patch by Sergey Matveev

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@176249 91177308-0d34-0410-b5e6-96231b3b80d8