Switch from unittest2.expectedFailure to our own decorator on TestSTL

the main reason is that our decorator contains extra fluff to "expect" crashes (which seem to
happen occasionaly on the android buildbot).

llvm-svn: 263633

lldb/packages/Python/lldbsuite/test/lang/cpp/stl/TestSTL.py

@@ -24,8 +24,7 @@ class STLTestCase(TestBase):
         self.source = 'main.cpp'
         self.line = line_number(self.source, '// Set break point at this line.')
 
-    # rdar://problem/10400981
-    @unittest2.expectedFailure
+    @expectedFailureAll(bugnumber="rdar://problem/10400981")
     def test(self):
         """Test some expressions involving STL data types."""
         self.build()