Xfail TestConcurrentTwoWatchpointsOneSignal on arm

r317561 exposed an interesting bug (pr35228) in handling of simultaneous
watchpoint hits. Disabling the test until we can get that fixed.

llvm-svn: 317683

lldb/packages/Python/lldbsuite/test/functionalities/thread/concurrent_events/two_watchpoints_one_signal/TestConcurrentTwoWatchpointsOneSignal.py

@@ -15,6 +15,7 @@ class ConcurrentTwoWatchpointsOneSignal(ConcurrentEventsBase):
     @skipIfFreeBSD  # timing out on buildbot
     # Atomic sequences are not supported yet for MIPS in LLDB.
     @skipIf(triple='^mips')
+    @expectedFailureAll(bugnumber="llvm.org/pr35228", archs=["arm", "aarch64"])
     @add_test_categories(["watchpoint"])
     def test(self):
         """Test two threads that trigger a watchpoint and one signal thread. """