Mark two more tests as FLAKY

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@350692 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/adopt_lock.pass.cpp b/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/adopt_lock.pass.cpp
index 8327100..79c639e 100644
--- a/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/adopt_lock.pass.cpp
+++ b/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/adopt_lock.pass.cpp
@@ -9,6 +9,8 @@
 //
 // UNSUPPORTED: libcpp-has-no-threads
 
+// FLAKY_TEST
+
 // <mutex>
 
 // template <class Mutex> class lock_guard;
diff --git a/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.pass.cpp b/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.pass.cpp
index 97f9d07..4a2db39 100644
--- a/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.pass.cpp
+++ b/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.pass.cpp
@@ -9,6 +9,8 @@
 //
 // UNSUPPORTED: libcpp-has-no-threads
 
+// FLAKY_TEST
+
 // <mutex>
 
 // template <class Mutex> class lock_guard;